ugi EPA Cnemical Handbook Col Process Facli ies ive VOC E issions from ::rol Techniques TOr Development Agency Cincinnati, OH 45268

Transcription

1 States United Protection Environmental of Research and Office Development Handbook ::rol Techniques TOr Col EPA/625/R-93/ March Cincinnati, OH Agency EPA ive VOC E issions from ugi Process Facli ies Cnemical

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3 for Environmental Research Information Center of Research and Development Office Environmental Protection Agency U.S. Ohio Cincinnati, AI6251R EP 1994 March Handbook Techniques for Control VOC Emissions from Fugitive Chemical Process Facilities Printed on Recycled Paper

4 information in this document has been funded wholly, or in part, by U.S. Environmental Agency (EPA) under Contract No. 68-C1-0018, Work Assignment No. B-9, issued to Protection Environmental Services, Inc. (PES), as a subcontractor to Eastern Research Group, Inc. Pacific This document has been subjected to EPA's peer and administrative review and has been (ERG). approved for publication as an does not constitute endorsement or recommendation for use. Notice EPA document. Mention of trade names or commercial products

5 document was prepared under Contract No. 68-C1-0018, WA No. B-9, by Pacific Environmen- This Services, Inc. (PES), as a subcontractor to Eastern Research Group, Inc. (ERG), and under tal of U.S. Environmental Protection Agency (EPA). Justice A. Manning of EPA sponsorship of Research and Development, Center for Environmental Research Information, Office was officer responsible for preparation of this document. Special acknowledgment is project Couturier and David Markwordt of EPA Office of Air Quality Planning and Standards Daniel ir assistance, comments, and technical review of early drafts of this Handbook and for to individuals who responded so generously to our information and reference requests. numerous helpful comments were received from American Petroleum Institute's Air Toxics Multi-Year Very Force. Representatives from Chemical Manufacturer's Association also reviewed Task report. Participating in development of this document for PES draft Eric Hollins, John were: Kenneth Meardon, Paul D. Koch, Andrew Weisman, and Nancy Golden. Also, Douglas Chehaske, Acknowledgments given to Coggeshall, formerly with Dresser Valves, is extended appreciation for technical review and A. comment. iii

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7 List of Figures... vii Acronyms... ix 1 Chapter Chapter Chapter Chapter Introduction 1... Objectives Handbook Emission Control Techniques VOC Organization Handbook References... 4 Regulated Source Categories 6 Federally Regulation of VOC Sources 25 State Sampling Connections Flanges and Or Connectors Agitators Systems and Control Devices 35 Closed-Vent Monitoring Instruments Contents Page List of Tables... VIII Requirements for Fugitive Emissions 5 Regulatory Introduction 5... References Regulated Equipment Pumps Compressors Pressure Relief Devices Lines.or Open Valves 32 Open-ended Valves Process Product Accumulator Vessels References Monitoring Requirements Overall Survey Procedure Screening Protocols V

8 4 Chapter Chapter Chapter Chapter 7.1 Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Appendix H Appendix J Appendix K Requirements (continued) Monitoring Handling 46 Data Procedures for Quality Assurance 47 Calibration 47 References and NESHAP Equipment Leak Records and Reports 49 NSPS 49 Recordkeeping 50 Reporting 53 References Management Systems 55 Data Data Management 55 Manual Data Management 57 Automated 57 Reference. Considerations 65 Engineering Emission Estimates 65 Developing References 72 Methods 21 and Response Factors 105 Example Initial Semiannual NSPS Report 123 Example Semiannual NSPS Report 127 Semiannual NESHAP Report (illustrating a skip program and a Example valves program) 137 difficult-to-monitor Example Semiannual NESHAP Report (closed-vent system; itemized revisions) 143 Sample Forms 149 Contents (continued) Chemical Processes Affected by Proposed HON Regulation 73 Volatile Hazardous Air Pollutants (VHAPs) Covered by HON 87 Example Semiannual NESHAP Report (illustrating a pump repair record) 117 Example Benzene Semiannual NESHAP Report 131 Appendix vi

9 model flow diagram LDAR of simple packed seal Diagram Diagram of basic single mechanical seal arrangements of dual mechanical pump seals 28 Typical of seal-less canned-motor pump Diagram of diaphragm pump Diagram designs of mechanical compressor seals 30 Typical design of a pressure relief valve mounted Typical a rupture disc device 32 on of two closed-loop sampling systems Diagram of a ball valve Diagram of a sealed bellows valve Diagram Diagram of a weir diaphragm seal 34 precision for portable VOC detectornld# 58 Calibration calibration for portable VOC detector--id# '.. 59 Instrument identification form Pump monitoring form Equipment and difficult-to-monitor valves 62 Unsafedetection report Leak Strategy for estimating emissions from equipment leaks 66 List of Figures Figure Page Diagram of a spring.loaded relief valve Diagram of a globe valve with a packed seal Diagram of a bonnet diaphragm seal Primary valve maintenance points vii

10 Reduction Efficiencies for SOCMI Valves and Pumps Based 1-1 LDAR Model 2 on NSPS and CTG Control Levels for SOCMI Fugitive Emissions NSPS Equipment Leak Standards---Affected Facility Definitions Process Unit Definitions--Specific Qualifiers Performance Criteria for Portable VOC Detectors Portable VOC Detection Instrument Performance Specifications Average Emission Factors for Fugitive Emissions Leaking and Nonleaking Emission Factors for Fugitive Emissions ' Estimate of "Uncontrolled" Fugitive Emissions for 7-3 Hypotical Case 68 a Stratified Emission Factors for Equipment Leaks Estimate of Fugitive Emissions Using Stratified Emission Factors for 7-5 Hypotical Case 69 a Prediction Equations for Nonmethane Leak Rate for Valves, Flanges, and Pump Seals in 7-6 Process SOCMI Default Zero Values and Emission Rates Chemical Processes Affected by Proposed HON Regulation 74 A-1 Volatile Hazardous Air Pollutants (VHAPs) Covered by HON 88 B-1 Response Factors for Foxboro OVA-108 and Bacharach TLV Sniffer at 10,000 D-1 Response 106 ppmv Tested Compounds Which Appear To Be Unable To Achieve D-2 Instrument Response of an ppmv at Any Feasible Concentration ,000 Response Factors for AID Model 580 and Model 585 Photoionization Type Organic D-3 Response Factors for MIRAN Model 1N80 Infrared Analyzer 111 D-4 Response Factors for HNU Systems, Inc., Model P1-101 Photoionization Analyzer 116 D-5 National Emissions Standards for Hazardous Air Pollutants Benzene Equipment Leaks, E-1 KAR 57: Devices Found Leaking During Quarterly Monitoring Required Under 401 KAR 61: E-4 NSPS-VOC Leak Monitoring Results, July-December G-1 G-2 NSPS-VOC Process Units' Downtime Summary, July-December List of Tables Table Page 2-1 Effect of Equipment Leak Controls NSPS Regulations0 CFR Part Equipment Definitions Recordkeeping Requirements Reporting Requirements Fugitive Emission Sources Example of a Datasheet Illustration of Skip-Period Monitoring Bagging Strategies Vapor Analyzers E-2 Dates of Process Unit Shutdowns E-3 Additions/Deletions viii

11 ASTM BDT CAAA CO CTG EE EPA FID GC HL HON ID LDAR LEF LL Mg N NAAQS NDIR NESHAP NGL NLEF NOx NSPS O OVA PCL PID PRV PSD RACT RCRA RF SARA SIP SOCMI TLV TSDF VHAP VOC Air Act Amendments of 1990 Clean monoxide carbon dioxide carbon techniques guideline control estimate emission Environmental Protection Agency U.S. ionization detector flame chromatograph gas liquid heavy organic NESHAPs hazardous identification detection and repair leak emission factor leaking liquid light megagram nitrogen ambient air quality standard national infrared nondispersive emission factor nonleaking oxides nitrogen source performance standard new oxygen vapor analyzer organic of sources found leaking percent detectors photoionization relief valve pressure of significant deterioration prevention available control technology reasonably Amendments and Reauthorization Act Superfund implementation plan state organic chemicals manufacturing industry syntic limit value threshold storage, and disposal facility treatment, hazardous air pollutant volatile Acronyms Society for Testing and Materials American demonstrated technology best 2 CO emissions standards for hazardous air pollutants national gas liquid natural Conservation and Recovery Act Resource factor response volatile organic compound ix

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13 Handbook Objectives 1.1 for controlling fugitive volatile organic.techniques emission standards, such as those outlined in stringent hazardous organic national emissions standards for air pollutants (HON) emission regulations hazardous FR 62607) proposed December 31, As (57 control techniques become more complex, emission need for guidance on complying with emission becomes more important. This handbook is standards general guide to emission control strategies that can a implemented under existing regulations. Most of be strategies will be applicable under HON se but more stringent HON limits may regulations, controls. handbook contains a require-additional review of established new source performance detailed (NSPSs) and national emissions standards standards hazardous air pollutants (NESHAPs), as well as for on Resource Conservation and information storage, and disposal facilities (TSDFs); treatment, state requirements; and HON standards. additional handbook is intended to assist small- to medium- businesses and industries that are subject to sized VOC Emission Control Techniques 1,2 single emission control technique can be used for all No into two categories: equipment practices and separated practices. work practices involve Equipment or eliminate emissions. A reduce equipment to example is common incinerator, that is an to reduce organic emissions from a process vent. used equipment controls include 1) leakless technology Or valves and pumps; 2) plugs, caps, and blinds for for lines; 3) rupture discs and soft seats (O- open,ended for pressure relief valves (PRVs); 4) dual rings) seals with non-voc barrier fluid/degassing mechanical 1 Chapter Introduction systems for rotary equipment; 5) closed-loop vent systems; and 6) enclosure of seal area/vent sampling a combustion control device for dynamic seals. to equipment controls generally can attain up to se percent reduction of emissions. Mechanical seals 100 techniques that rely upon combustion control have and assigned an overall control efficiency of 95 been which is consistent with efficiencies percent, practices refer to plans and procedures Work to reduce or estimate emissions. Work undertaken are most commonly used control practices for equipment leaks. primary work techniques applied to pressure relief valves, or valves, practice and or Sources is leak detection and repair pumps, of sources (U.S. EPA, 1986, p. 4-1). (LDAR) emissions reduction potential for LDAR is highly frequency of monitoring (surveying) sources for and threshold definition of a leak. A monthly leaks plan is generally more effective than a monitoring monitoring plan in reducing emissions, since quarterly more effective than a system that responds only to is leaks. larger of individual sources can affect Characteristics reduction achieved by LDAR. Important emissions include leak occurrence rate, leak characteristics rate, accessibility of leaking equipment, recurrence repair effectiveness. Using specific source and control effectiveness can be evaluated characteristics, different monitoring plans using LDAR Model for et al., 1981), a set of recursive equations (Williamson operates on an overall population of sources. In that model, sources are segregated into following this subgroups for any given monitoring interval: 1) sources leak due to leak occurrence rate; 2) sources that leak and cannot be repaired below 10,000 that leak definition; 3) sources that leaked, were ppmv successfully, but leaked again soon after repaired (VOC) emissions from chemical process compound are evolving continually to meet increasingly facilities to or frequently applied recovery assigned (U.S. EPA, 1986, p. 4-1). techniques Work Practices variable and depends upon several factors, Recovery Act (RCRA) standards for hazardous waste including are found and corrected more quickly. Similarly, a leaks system that corrects smaller leaks usually maintenance NSPSs, NESHAPs, and or pertinent regulations. leaks (U.S. EPA, 1986). techniques equipment to control emissions from equipment leaks can be used Equipment Practices use of an add-on control device, such as

14 10,000 ppmv leak definition). relative below of sources in each subgroup change with numbers monitoring interval step, based on each for sources. se subgroups, and characteristics manner in which y interact according to source characteristics, are shown in Figure individual (U.S. EPA, 1980). 1-1 monitoring plans, such as plan permitted Complex by EPA under its equipment leak standard for valves in syntic organic chemicals manufacturing industry can be examined using LDAR Model. (SOCMI), plan allows quarterly monitoring of all valves, SOCMI by monthly monitoring of those valves supplemented leaked and were repaired (U.S. EPA, 1980). that in Table 1-1 are results of simple Presented quarterly, semiannual, and annual LDAR monthly, published by EPA for valves and pumps in modeling monthly/quarterly hybrid program allowed SOCMI. EPA for valves also is shown. se results indicate by as monitoring frequency increases, so does that, emissions reduction. Furrmore, anticipated indicate some instances with no substantial results in reducing emissions, because monitoring advantage repair are too infrequent. Such results, however, and subject to interpretation for specific cases, since are 1-1. Reduction Efficiencies for SOCMI Valves and Table Based on LDAR Model Pumps Type Source Valves, Light Interval Valves, Gas Liquid Monitoring Monthly Monthly/quarterly* Quarterly (0.076) Semiannual components. Numbers in parenses indicate a negative control efficiency. Note: numbers are generated when occurrence rate for Negative interval exceeds initial leak frequency. Negative results monitoring subject to interpretation and may not be meaningful (U.S. EPA, are p. 4-7). 1986, ability to model results of LDAR programs means to examine alternative standards provided valves. LDAR Model was used to consider for LDAR programs for process units exhibiting monthly assqciated decline occurs in average emission an and in emissions. Coupling this information with factor costs of LDAR program and analyzing resultant values led to selection of 2 cost-effectiveness units with low leak rates (and low leak process were given a special provision in frequencies) for SOCMI fugitive VOC emissions (U.S. EPA, NSPS 1982). reductions for equipment leak control Emission can be extremely variable, particularly for techniques practices like leak detection and repair programs. work terms of standard-setting activities, criteria for In of a given control technique or a particular selection of control (e.g., monitoring interval of a leak level and repair program) can be quite different. detection example, criterion used in establishing best For levels of control are compared for VOC NSPS leaks (fugitive emissions) for SOCMI; equipment control effectiveness values also are associated (U.S. EPA, 1986, p. 4-6). presented Handbook Organization 1.3 focus of each handbook chapter is summarized Chapter is a general introduction containing a of emission control techniques, detailing discussion intent of handbook, and describing of each specific chapter. contents Addressed in Chapter 2 are existing regulatory for fugitive VOC emissions. se requirements federal regulations such as NSPS, include and RCRA standards; certain state NESHAP, of 1977 and 1990; and HON Amendments NSPS regulations apply primarily to four standards. categories: SOCMI, petroleum refineries, source natural gas processing plants, and certain onshore equipment leaks of volatile hazardous air (VHAPs). in Chapter 3 are specific pieces of Outlined covered by equipment leak standards. equipment equipment covered includes pumps, compressors, (i.e., those that experienced leak recurrence); repair 4) sources that do not leak (i.e., those screening and Consequently, percent leaking as performance limit Summary of Emission Reductions NSPS might not demonstrated technology (BDT) for be best criterion for selecting necessarily available control technology (RACT) reasonably in control techniques guidelines (CTG) presented used by states. In Table 1-2, CTG and documents are based on average input values for an entire y (U.S. EPA, 1986, p. 4-4). industry below: Pumps, Light Liquid 0.24 (0.19) (0.80) Annual monitoring with quarterly monitoring of "low leak" Monthly such as state implementation regulations (SIP) revisions required by Clean Air Act plan manufacturing plants. NESHAP regulations polymer to sources of benzene and vinyl chloride apply pollutants low leak frequencies. With decreasing leak frequency, pressure relief devices, sampling connections, open

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16 Table 1-2. NSPS end CTG Control Levels* for SOCMI Fugitive Emissions (U.S. EPA, 1986, p. 4-8) Source Control Technique Reduction Control Technique Reduction Valves, gas Pressure relief valves, gas Open-ended lines Sampling connections leak detection and repair Quarterly leak detection and repair Quarterly se and or control techniques are discussed in Chapter 3. and open-ended lines, process valves, valves product accumulator vessels, flanges/connectors, Described in Chapter 4 are monitoring or requirements for various equipment screening Protocols/methodologies for imple- components. and conducting monitoring programs are menting Also addressed are selection, of discussed. organic analyzers and various methods of portable Presented in Chapter 6 are various techniques for and maintaining vast amounts of data organizing by monitoring programs. Both manual generated automated data management approaches are and Example data sheets and example reports reviewed. are provided. also Chapter 7 contains information on certain engineering that should be considered when managing issues estimating VOC emissions include applying EPA for emission factors, using a leak/no-leak average Monthly leak detection and repair 61 Monthly leak detection and repair 73 Monthly leak detection and repair 59 disk, soft seats (O-rings), 100 Rupture to control device vented Plugs, caps, blinds, etc. 100 Seal enclosed/vented to control device 100 Port Royal Road 5285 VA Springfield, EPA U.S Environmental Protection Agency. U.S. factors for equipment leaks of VOC and Emission EPN450/3-86/O02. NTIS PB HAP. Triangle Park, NC. Research EPA U.S. Environmental Protection Agency. U.S. emission sources of organic compounds--- Fugitive information on emissions, emission. additional and costs. EPN450/3-82/010. NTIS reductions, EPA U.S. Environmental Protection Agency. U.S. report: Frequency of leak Problem-oriented for fittings in syntic organic chemical occurrence process units. EPN600/2-81/O03. NTIS PB81- plant Control Techniques Guidelines New Source Performance Standards Percent Percent Pumps, light liquid Light liquid Quarterly leak detection and repair Quarterly leak detection and repair Plugs, caps, blinds, etc. IO0 Compressors Quarterly leak detection and repair Closed purge sampling 100 References 1.4 an NTIS number is cited in a reference, that When document is available from: and closed-vent systems and control agitators, devices. National Technical Information Service handling. data Delineated in Chapter 5 are recordkeeping and requirements mandated by NSPS and reporting equipment leak standards. Methods for NESHAP good records are discussed, and maintaining report formats are provided. example PB Research Triangle Park, NC Research Triangle Park, NC. H.J., L.P. Provost, and J.I. Steinmetz Williamson, for evaluating effects of leak detection and Model VOC emissions, including methods for fugitive emission estimates. Strategies suggested developing programs on fugitive emissions. Technical repair DCN Radian Corporation, Note Austin, TX. September. applying stratified emission factors, approach, leak rate/screening value correlations, employing and using unit-specific correlations.

17 2 Chapter Requirements for Fugitive Emissions Regulatory leak standards are designed to reduce or Equipment VOC or VHAP emissions from certain eliminate equipment leaks. For example, seals designed process keep process fluids in pumps could fail, allowing to process fluid to leak into VOC-containing Equipment leak standards specify certain environment. and maintenance practices intended to monitoring or eliminate se leaks and resultant reduce criteria pollutants for which a national ambient air of standard (NAAQS) is designated under Section quality of Clean Air Act, and nonattainment of 109 NAAQS is a serious problem in United ozone formation of ozone can be abated by States. amount of VOCs and NOx emitted and by reducing VOC and NOx exposure to ultraviolet radiation. reducing federal and state regulations contain equipment Both standards for VOC emissions. Equipment leak leak for VHAP emissions are contained in federal standards only. VOC emissions from stationary regulations (process vents or stacks, and fugitive or sources state administration of federally mandated control for and can modify federal standards. In programs one source category (Hazardous Waste, addition, Storage, and Disposal Facilities) is Treatment, quality goals, primary goals of NSPSs are to air emissions at all new and modified sources, minimize development of new pollution problems, prevent enhance air quality as nation's industrial base and replaced. Equipment leak standards will limit VOC is from all new, modified, or reconstructed emissions units and will limit future emissions. Even process se reductions might not apply directly to though enable continued industrial growth while preventing will air quality problems. NSPSs.complement future of significant deterioration (PSD) and prevention rules as a means of achieving and nonattainment NAAQS; on a broader basis, NSPSs maintaining new. sources from exacerbating.air pollution prevent regardless of existing ambient air quality. problems, are controlled because such air pollutants can VHAPs a health risk for humans. Benzene and vinyl pose two VHAPs regulated by equipment leak chloride, are known human carcinogens. standards, rule for HON emission standards greatly proposed are described in more detail later in this chapter. 1994, equipment leak standards were estimated to Federal VOC emissions between 55 and 68 percent reduce facilities affected by standards. EPA has from se estimates cover 5-year period (typically from 1980 to 1985). For a EPA estimated that approximately 830 newly example, modified, or reconstructed facilities constructed, by SOCMI equipment leak standards by 1985 affected emit approximately 91,500 tons per year (tpy) of would VOC emissions if left unregulated. After control, fugitive 830 facilities were estimated to emit 40,700 tpy of se VOCs from equipment leaks--a 56 percent fugitive Presented in Table 2-1 are EPA estimates of reduction. and controlled emissions from refineries, uncontrolled plants, and facilities that use benzene (U.S. SOCMI 1990a). emission reduction percentage for EPA, refineries is approximately 63 percent and petroleum benzene sources, 68 percent. for Federal Regulations regulations consist of NSPSs, NESHAPs, and Federal under RCRA. NSPSs are implemented standards Section 111 of Clean Air Act and apply to under constructed stationary sources--those sources newly after date that an NSPS is proposed in constructed 2.1 Introduction emissions. fugitive along with nitrogen oxides (NOx) and ultraviolet VOCs, one radiation, contribute to ozone production. Ozone is scope of VHAP regulations. proposed expands standards, which probably will be promulgated in HON estimates of uncontrolled and controlled developed from newly constructed, modified, and emissions reconstructed source facilities. leaks) are regulated primarily under NSPSs, equipment and SIPs. SIPs generally provide basis NESHAPs, under RCRA. regulated y do support achievement of ambient Although attainment or nonattainment of ozone NAAQS, y

18 of Equipment Leak Controls (U.S. EPA, Effect 1990a) Source Category Uncontrolled After Control Refineries* 53,900 19,800 Benzene 8,700 2,750. estimates only include plants subject to NSPS se regulafions. Federal Register. In addition, existing stationary (sources existing prior to NSPS proposal sources can become subject to an NSPS if y are date) or reconstructed after NSPS proposal date. modified degree of national uniformity to air pollution standards A established through NSPSs. Such uniformity tends to is preclude situations in industries as a result of relaxed standards, relative new or states. to disease-causing agents. Formerly, y were serious and implemented for individual pollutants, developed this proved to be an extremely cumbersome and but process. By 1990, NESHAPs had been slow-moving for only eight pollutants. Of se, established leak regulations were applied only. to equipment and vinyl chloride. Clean Air Act benzene of 1990 (CAAA) have changed Amendments for controlling hazardous air pollutants. In approach 189 chemicals are identified as air toxics that will CAAA, controlled on a source category basis. A subset of be listed chemicals is being considered for regulation proposed HON standards (see discussion in under of this chapter). Section a class, organic air emissions at hazardous waste As are regulated under Subtitle C of RCRA. Final TSDFs (e.g., pumps and valves) that contains or equipment hazardous waste streams with 10 percent or contacts total organics. final standards incorporate, or more follow, many of provisions of equipment- closely NSPS and benzene NESHAP. se leak are promulgated under authority of Section standards of Hazardous and Solid Waste Amendments 3004 RCRA and are incorporated into Parts 264 and 265 to leaks of VOCs from existing stationary equipment States containing areas that fail to meet sources. address VOC control by revising ir SIPs. to Air Act Amendments of 1977 and 1990 require Clean for nonattainment areas to include RACT SIPs for stationary sources. requirements states have regulations in place (or under Several for syntic organic chemical and development) (U.S. EPA, 1988). Some states also are equipment pumps/compressors and valves/flanges regulating A general overview of role of states independently. adopting, modifying, and enforcing state VOC in Federally Regulated Source 2.2 Categories four NSPSs are found in 40 CFR Part 60, which federal regulations pertaining to protection contains environment. Part 60 contains standards of of for new stationary sources, and specific performance SOCMI equipment leak standards are in VV of 40 CFR Part 60, and sections ( ) of Subpart Equipment leak standards for polymer manufacturing are in Subpart DDD, through industry noted, NSPSs apply primarily to As newly constructed State Regulations Table 2-1. In addition to federal regulations, some states regulate Nationwide Emissions (tpy) NAAQS for ozone (nonattainment areas) are required SOCMI 91,500 40,700 manufacturing equipment, natural gas/ polymer processing plants, and petroleum refinery gasoline regulations is presented in Section 2.3 of this chapter. which certain states could attract which are implemented under Section 112 NESHAPs, Clean Air Act, apply to both new and existing of Sources Subject to NSPSs As of June 1, 1992, following four source categories sources. NESHAPs are intended to control stationary pollutants such as carcinogens or or hazardous are regulated by NSPSs for equipment leaks of VOCs: SOCMI Petroleum refineries Onshore natural gas processing plants Certain types of polymer manufacturing plants for new stationary sources are within regulations subparts, as follows: various standard are found in through this petroleum refinery equipment leak standards rule to limit leaks from standards are established in in Subpart GGG, through are onshore natural gas processing plant equipment Subpart KKK, through leak standards are in (Subpart BB), Air Emission Standards for Owners and of Hazardous Waste Treatment, Storage, Operators Disposal Facilities (U.S. EPA, 1990b). and sources and apply to existing sources only when y are modified or reconstructed. Consequently,

19 applicability dates, which identify NSPSs' effective dates, distinguish between new standards' proposal.) NSPSs become effective upon of Proposal and promulgation dates for promulgation. regulations are presented in Table 2-2. Each NSPS also exempts certain sources, equipment, or regulation units from entire regulation or portions process se exemptions are identified in following reof; for each NSPS regulation and in Section section sources subject to NESHAPs. for SOCMI--Subpart VV 1/5/81 10/18/83 Refineries--- 1/4/83 5/30/84 Petroleum GGG Subpart Natural Gas 1/24/84 5/24/85 Onshore Plants-- Processing Plants--Subpart DDD Syntic Organic Chemicals Industry Manufacturing is a broad source category that covers plants SOCMI produce many types of organic chemicals (U.S. that 1984a; 1982a,b; 1980). This industry segment EPA, products that are derived from about 10 generates petrochemical feedstocks and are used as basic in a number of syntic products feedstocks Examples of organic chemicals produced in. industries. SOCMI segment are acetone, methyl methacrylate, and glycine. complete list of organic toluene, covered by SOCMI equipment leak chemicals can be found in of 40 CFR Part 60 standards EPA, 1984b). (U.S. SOCMI rule covers industries that produce, as or final products, one or more of intermediates listed in standards apply to chemicals affected facility that commenced construction or any after January 5, SOCMI rule modification affected facility as "group of all defines within a process unit," and such equipment is covered if it is in VOC service (as defined equipment Section ). following exemptions are in in SOCMI rule: identified Any affected facility that has design capacity to less than 1,000 megagrams (Mg) (1,100 produce to control se emissions would be cost high. This lower production rate cutoff unreasonably based on cost and emission reduction was Explanation of analysis is found considerations. Section 5.7 of background information in for promulgated standards (U.S. EPA, document 1980). an affected facility produces heavy liquid ff in petroleum refinery studies, equipment obtained VOCs with vapor pressures above processing kpa (0.04 psi) leaked at significantly higher rates 0.3 frequencies than equipment processing VOCs and vapor pressure below 0.3 kpa. EPA elected, with to exempt equipment processing lower refore, pressure VOC substances from routine vapor requirements of standards (U.S. EPA, LDAR p. 5-21). Even though standards do not 1982b, monitoring equipment in heavy liquid service require leaks, standards require VOC leaks from this for detected visually or orwise, to be equipment, within 15 days if a leak is confirmed when repaired EPA Reference Method 21 (see Chapter 4 for using information on RM-21). more affected facility that produces beverage alcohol Any exempt from During public comment is on proposed rule, EPA received comments period beverage alcohol producers saying that y from be exempt from coverage by standards should beer and whisky producers were exempted because priority list. EPA concluded that process from within beer and whisky plants that are units fermented beverages solely for purposes producing Any process unit in beer and whisky standards. however, that is used to manufacture plants, nonbeverage fermented products (e.g., a to produce industrial grade alcohols from train products) is subject to standards fermentation EPA, 1982b p. 1-12). (U.S. affected facility that has no equipment in Any is exempt from EPA grants an service to any SOCMI unit that does not process exemption products without use of VOCs; however, ir units are expected to be exception rar se in vacuum service is excluded from Equipment of to ( LDAR requirements if a list of identification numbers for requirements) equipment is recorded in a log that is kept in a such facilities) have production rates so development that ir VOC emissions from equipment small be very small. Consequently, date and existing sources. ( applicability date is leaks are likely to only from heavy liquid feed or raw chemicals it is exempt from Based on data materials, Table 2-2. NSPS Regulations--40 CFR Part 60 Proposal Promulgation Date Regulation Date KKK Subpart Manufacturing 9/30/87 12/11/90 Polymer of human consumption should be exempt from distillation VOC might produce VOCs. A few SOCMI process units than rule. per year is exempt from , which tons) specific requirements of LDAR contains regulations. Some process units (e.g., research and 7

20 accessible location ( (e)(5)). EPA readily covering sources in vacuum service as judges vacuum would have little, if any, potential to slight VOCs. "In vacuum service" means that emit is operating with an internal pressurethat equipment at least 5 kpa (0.7 psi) below ambient pressure. is defining SOCMI-affected facilities, EPA considered In each equipment component (such as each selecting situations would arise in which replaced however, components in existing process units would equipment subject to standards while adjacent components be not be subject to standards. With such a would Furr, cost of implementing an LDAR costly. for a very small portion of all equipment program standards in this subpart apply to any affected that commenced construction or modification facility refineries are defined in applicable Petroleum leak standard as: equipment or or products through distillation lubricants, petroleum or through re-distillation, cracking, of NSPS specifies that affected facilities covered by This equipment leak standards for $OCMI (Subpart or for onshore natural gas processing plants VV), KKK), are excluded from se standards. (Subpart refineries, for example, produce organic Some on SOCMI list. Because se refineries chemicals sources of fugitive VOC emissions (such as have and valves) involved in producing one or more pumps chemicals, EPA believes that SOCMI $OCMI are applied appropriately to process units in standards refineries. To eliminate potential redundancy or se refore, process units covered under confusion, standards are exempted from refinery SOCMI For this NSPS, affected facilities include standards. compressor and group of all equipment each in ) within a process unit. (defined few compressors are located in petroleum Relatively in fact, many process units do not contain refineries; general, petroleum refineries have no spare In and compressors that are in place are compressors, Based on se considerations, EPA elected to compressor as an affected facility. (For all or each process unit is affected facility.) equipment, petroleum refinery NSPS allows owners or to define equipment as "in light liquid service" operators " percent evaporated is greater than 10 percent at if as determined by American Society for Testing 150 C, Materials (ASTM) Method D-86." This NSPS also and several exemptions ( ), including: contains Compressors in hydrogen service are exempted EPA's analysis of cost of controlling from in hydrogen service showed that compressors reductions from such compressors could emission be achieved at a reasonable cost. Thus, EPA not to exclude such compressors from decided Also exempt from and are in light liquid service and valves in gas pumps and light liquid service within a process unit service is located in Alaskan North Slope. Refineries that routine LDAR requirements, but are not exempt equipment requirements of standards. from Subpart KKK of 40 CFR Part 60 applies to in equipment that is located at onshore natural leaks processing plants (U.S. EPA,.1983a,b). gas apply to any affected facility that commences standards reconstruction, or modification after construction, 20, Natural gas processing plants are January as "... processing (sites) engaged in defined of natural gas liquids from field, gas, extraction of mixed natural gas liquids to natural gas fractionation or both." Facilities covered by SOCMI or products, refinery equipment leak standards (Subparts petroleum and GGG, respectively) are excluded from VV KKK Subpart NSPS identifies two types of affected petroleum This facilities: 1) each compressor in VOC service or refinery wet gas service, and 2) group of all equipment in compressors defined in ) within a (except unit. Subpart KKK specifically includes any process station, dehydration unit, sweetening unit, compressor underground storage tank, field liquefied natural gas unit if it is located at an onshore or gas processing plant natural A compressor in a process unit is compressors. for use only within that specific process unit. designed inappropriate because sources operating even at a identifiable. Thus, keeping track of compressors readily by standards would not be too expensive. covered define this definition were selected, pump and each valve) If mixture of new and existing components, effort to track of those equipment components covered by keep standards and those not covered would be quite at a plant site would be very costly. For components reasons, this definition was rejected. se standards Petroleum Refineries GGG of 40 CFR Part 60 applies to equipment Subpart in petroleum refineries (U.S. EPA, 1982c, 1978). leaks Alaskan North Slope are exempt from located in after January 4, Onshore Natural Gas Processing Plants engaged in producing gasoline, (facilities) distillate fuel oils, residual oils, kerosene, equipment or reforming of unfinished petroleum derivatives. gas garing system, 8

21 proposing Subpart KKK, EPA defined "in VOC When using a 1.0 weight percent VOC limit (rar service" 10 weight percent). 1.0 weight percent VOC than was chosen to ensure that inlet (wet) gas streams limit subject to NSPS controls, since emissions can be were at reasonable costs from inlet gases. Based reduced on received on proposed standards, comments EPA agreed that a 1.0 weight percent limit however, inappropriate for dry gas streams. EPA selected a was concentration limit of 10 weight percent in final VOC VOC service" definition and decided to equipment in wet gas service (except for wet include reciprocating compressors) by covering it as a gas "In wet gas service" means that a piece of class. contains or contacts field gas before equipment to use alternative definitions for "in owner/operators liquid service" and "in light liquid service." An heavy or operator may define equipment as in heavy owner service if weight percent evaporated is 10 liquid or less at 150 C, as determined by ASTM percent D-86. An owner or operator may define Method as in light liquid service if weight percent equipment is greater than 10 percent at 150 C, as evaporated NSPS generally requires owners and operators to This provisions found in 40 CFR Part 60, Subpart follow (Equipment Leaks for SOCMI), with exceptions VV follows: as Sampling connection systems are exempt from Pumps in light liquid service, valves in gas/vapor and in light liquid service, and pressure relief service in gas/vapor service that are located at a devices plant with a design capacity to nonfractionating, <10 million standard cubic feet per day (scfd) process field gas are exempt from routine monitoring of of (a)(1), (a), and requirements Small, nonfractionating plants often (b)(1). unmanned or are operated by personnel operate. necessary ability to carry out a lacking responsible LDAR program. In personnel or an outside consultant would be office to conduct LDAR. EPA examined required costs that would be incurred in such cases additional amount of resultant emissions reductions and change from reasonable to at plants with capacities between 5 unreasonable 10 million scfd. refore, EPA decided to and any nonfractionating plant with a design exempt of <10 million scfd of field gas from capacity monitoring requirements for valves, pumps, routine pressure relief devices. Neverless,. all and plants, regardless of capacity, are fractionating to implement routine monitoring required requirements. in light liquid service, valves in gas/vapor Pumps and in fight liquid service, and pressure relief service in gas/vapor service within a process unit devices routine monitoring requirements of (a), and (b)(1). EPA 2(a)(1), comments on natural gas plant operations reviewed North Slope of Alaska and determined that in to comply with certain aspects of proposed costs would be unreasonable. LDAR programs standards higher labor, administrative, and support costs incur plants that are located at great distances from at population centers and particularly those that major extremely low temperatures, as in experience Thus, EPA decided to exempt plants located Arctic. North Slope of Alaska from routine LDAR in requirements were determined by EPA to be or and, refore, requirements still reasonable apply. compressors in Reciprocating not have an existing control device. cost did of installing and operating a control effectiveness for such compressors was high. cost device of controlling wet gas reciprocating effectiveness however, given that average cost reasonable, (combining cost-effectiveness numbers effectiveness centrifugal and reciprocating compressors) was for to be much lower ($460/Mg). Since estimated of Subpart KKK, however, several industry proposal commented that many gas plants, representatives small ones, will use reciprocating especially almost exclusively. For such plants, compressors control cost effectiveness would be compressor same as cost effectiveness for essentially only wet gas reciprocating compresso, rs plants with an existing control device (i.e., $1,700/ at This cost effectiveness, when considered Mg). of overall compressor control. representative for small plants, was judged by EPA to be costs high, so EPA revised standards to unreasonably all wet gas reciprocating compressors. exempt Reciprocating compressors used in service and all centrifugal compressors in wet (NGL) or NGL service, however, still are required to be gas located in Alaskan North Slope are exempt from rule for =in step. extraction onshore natural gas process plant NSPS allows EPA excluded se plants from only requirements.. routine LDAR requirements; costs of determined by ASTM Method D-86. wet gas service are from compressor control requirements of exempt When proposing Subpart KKK, EPA reciprocating compressors in wet gas exempted only if y were located at a gas plant that service at plants with an existing control device compressors of VOC reduced) was considered ($1,700/Mg se cases, central controlling and judged costs to natural gas liquids 9

22 with closed-vent systems because y equipped be controlled at a reasonable cost effectiveness. can process and fugitive emissions from polymer Both industry are regulated under Subpart manufacturing of 40 CFR Part 60 (55 FR 51035; U.S. EPA, DDD Equipment leak standards for VOCs have been 1984a). for those polymer manufacturing plants established produce polypropylene, polyethylene, polystyrene that terephthalate manufacturing processes polyethylene not covered under se standards. Any affected are with a design capacity to produce less than facility Mg/yr also is exempt. applicability date for 1,000 this NSPS, affected facilities are each group of For emissions equipment (as defined in ) fugitive any process unit (as defined in ). Fugitive within equipment includes each pump, compressor, emissions relief device, sampling connection system, pressure valve or line, valve, and flange or or open-ended in VOC service: A process unit is connector of equipment assembled to perform any of group and chemical operations in production of physical polyethylene, polystyrene, or one of ir polypropylene, storage facilities for product. Raw materials sufficient and monomer recovery are examples of handling equipment leak standards for polymer manufacturing incorporate most of SOCMI requirements facilities A limited exemption from equipment leak VV. applies to pumps in light liquid service that standards a "bleed port" (wherein polymer fluid is used to utilize lubrication and/or cooling of pump shaft provide consequently, exits pump), resulting in a and, leak of fluid. This exemption expires, however, visible existing pump is replaced or reconstructed. when as with petroleum refineries and natural gas Also, if percent evaporated is greater than service" percent at 150oC, as determined by ASTM Method 10 Sources Subject to NESHAP Regulations standards have been established for NESHAP leaks of two designated VHAPs--benzene equipment for a designated class of VHAPs will apply to standards specified group of production processes. a NESHAP standards are found in 40 CFR Part contains national emission standards for Part air pollutants, including following subparts: hazardous Subpart V contains national emission standard VHAP equipment leaks. This subpart contains for provisions and standards that apply to generic and vinyl chloride sources, as incorporated benzene reference in two subparts of 40 CFR Part 61 by specifically apply to se two pollutants. This that was added to regulations on June 6, subpart Subpart J specifies national emission standard equipment leaks of benzene and basically for Subpart J is found in through ). Subpart F contains various standards for vinyl vinyl chloride standards 61.65(b). promulgated in At that time, some were found in Subpart V. most recent standards was made on July 10, addition announcement of negotiated regulations for leaks of hazardous organics was published equipment FederalRegister(56 FR 9315) on March 6, in negotiated regulations are to be incorporated as se of HON emission standards, which were part on December 31, In addition to proposed leaks, HON standards will cover storage, equipment process vents, and wastewater emissions at transfer, national emission standards for equipment leaks of apply to pumps, compressors, pressure relief benzene sampling connection systems, open-ended devices, or lines, valves, and flanges and or valves that are intended to operate in benzene connectors (U.S. EPA, 1982d). Unlike NSPSs, se service benzene service" means that a piece of equipment "In contains or contacts a fluid (liquid or gas) that is eir least 10 percent benzene by weight, as determined at to provisions of (d). Methods for according Polymer Manufacturing Plants impact, and expandable), and copolymers of (crystal, three major polymer types. Equipment leaks from se equipment leak standards is September 30, meeting (U.S. EPA, 1990c) Subpart V as its standards. Subpart J incorporates added at same time as Subpart V (June 6, was in addition to equipment leak standards chloride, through 61.71). Equipment leak standards ( are found in emission sources were covered. At a later fugitive was revised to incorporate date, A process unit can operate independently copolymers. supplied with sufficient feed or raw materials and if process units. Subpart for equipment leaks of VOCs, as presented in chemical plants Benzene plants, affected facilities under this processing may define equipment as "in light liquid standard both new and existing sources, and standards apply to no initial applicability date separates new from existing sources. D-86. that a piece of equipment is not in benzene determining also are specified in (d). service and vinyl chloride. In addition, proposed HON 10

23 benzene equipment leak NESHAP contains exemptions: following Any equipment in benzene service that is located at plant site designed to produce or use less than a Mg of benzene per year is exempt from 1,000 of ( generic equipment requirements standards for hazardous air pollution sources leak are contained in 40 CFR Part 61, Subpart V, that invoked by requirements in this section.) are on proposed standards requested Commentors for certain small-volume or intermittent exemption uses. Because EPA exempts plants from benzene standard when cost of standard is high in comparison to achieved unreasonably reduction, EPA determined a cutoff for emission plants based on a cost and emission exempting analysis. Based on this analysis, EPA reduction that cost of complying with determined is unreasonable for plants in which standard emission reduction is about 4 Mg/yr. To benzene plants on this basis, EPA selected a exclude cutoff of 1,000 Mg/yr per plant site based minimum a benzene design usage rate or throughput. This on is expected to exempt most research and cutoff facilities and or small-scale development For plants with a benzene design usage operations. greater than 1,000 Mg/yr, EPA determined that rate cost of standard is reasonable. Any process unit that has no equipment in benzene is exempt from requirements of service Sources located at coke by-product plants are from standard. exempt Equipment that is in vacuum service is excluded requirements of to if from is identified as required in (e)(5) as being it vacuum service. in add vinyl chloride to list of substances covered by to V, national emission standard for Subpart leaks (fugitive emission sources), of equipment Part61. This standard was promulgated on 40CFR V substantively affected only valves and Subpart in vinyl chloride service; all or equipment in flanges to comply with equipment and work practice standards F with those in Subpart V. primary effect consistent to require a specific monitoring schedule, leak was and repair provisions for valves and flanges definition, and development if reactor used to research vinyl chloride processed in polymerize Equipment used in research and development is from some of Subpart F if reactor used exempted polymerize vinyl chloride processed in to has a capacity of greater than 0.19 m 3 (50 equipment gallons) and less than 4.07 m 3 (1,075 gallons). This exemption from 61.65, which contains includes for fugitive emission sources. standards Sections of Subpart F that remain applicable are: definitions. (b), (c), and (d)--some of 61.64(a)(1), for polyvinyl chloride plant reactors, standards mixing, weighing and holding containers, strippers, monomer recovery systems. and test requirements emission monitoring requirements emission report requirements initial requirements reporting requirements recordkeeping is demonstrated to be less than 2.0 percent is valves from following sections of Subpart V exempt CFR Part 61): (40 each piece of equipment (d)--requiring be marked in such a manner that it can be to distinguished from or pieces of readily equipment. (b), (a), monitoring period and method to be covering leak definition, and skip period. used, requirements recordkeeping requirements reporting subject to reporting and requirements found specifically in recordkeeping F. Subpart in chloride service. vinyl F contains several exemptions affecting Subpart subject to fugitive emission standards: equipment Subpart F does not apply to equipment used in has a capacity.of less than 0.19 m 3 (50 equipment gallons). Equipment in vacuum service is exempt. Any process unit in which percentage of leaking Vinyl Chloride F of 40 CFR Part 61, vinyl chloride Subpart affects plants that produce ethylene standards, vinyl chloride, and one or more polymers dichloride, any fraction of polymerized vinyl chloride containing (U.S. EPA, 1982e). On January 9, 1985, EPA proposed and (c)--standards for valves, 30, September facilities already controlled by Subpart F Subjecting to Such process units are still vinyl chloride service already was required by Subpart 11

24 Hazardous Organic National Emission Standards HON standards will apply to a number of emission and to equipment leaks at organic chemical points As noted in Section 2.2.2, portion of plants. rule that.addresses equipment leaks was proposed (56 FR 9315) on notice published in March 6, 1991, Based Register, equipment leak rules will apply to Federal group of 453 organic chemical manufacturing a y also will apply to some additional processes. that produce certain butadiene-, chlorine-, or processes or chemical groups are defined as VHAPs chemicals this rule (see Appendix B). under number of manufacturing processes listed under A HON standards also contain equipment subject to or NESHAP equipment leak standards. Wherever NSPS overlapping rules apply, HON standards will take such Petroleum refining processes, however, are precedence. covered by HON standards, and a separate ruling not be developed for se processes. HON standards for equipment.leaks, as currently will expand number of regulated considered, significantly. In addition, changes in facilities of affected equipment and leak thresholds definitions introduced in proposed standards; se are changes probably will expand range of proposed components subject to regulation at affected facilities. se standards have been proposed only, Since introduced by expected HON standards changes not addressed in this handbook. owned are of. any facility subject to equipment leak operator first should determine wher HON standards are applicable to his or her facility before standards any current NSPS or NESHAP guidance or using stardards. reference regulations for equipment leaks incorporate three types of standards: 1) performance standards, different applicable. defined in Clean Air Act, a "standard of As refers to an allowable emission limit (e.g., performance" limit on quantity of a pollutant emitted over a a specified time period or a of equipment leaks, EPA determined that sources standards are not feasible, except in performance at "no detectable emissions" or process permits set of certain control devices. only way to installation emissions from most equipment leak sources, measure as pumps, pipeline valves, and compressors, such be to use a baggingtechnique for each would in a process unit. EPA determined that component number of components and ir dispersion over large areas would make such a requirement large impracticable (U.S. EPA, 1980). economically performance standards were not possible for Because types of equipment, alternative standards also were some combination reof. equipment leak or contain all of se alternatives. standards standards of performance are included in Two equipment leak standards. first standard is current service, closed-vent systems, and valves vapor designated for no detectable emissions). A (specifically is demonstrated to be operating with no source emissions if a reading of less than 500 ppmv detectable background is indicated by a portable VOC- above instrumenl second standard of measuring systems (e.g., condensers and adsorbers) are recovery have control efficiencies of at least 95 percent. This to of performance (95 percent reduction), also is standard to enclosed combustion devices. applicable standards specify use, design, or Equipment of a particular piece of equipment. A operation is in compliance with use standards when component piece of equipment is used in a specified manner. example, open-ended lines or open valves are to For equipped with a cap, blind flange, plug, or second be Thus, an open-ended line that is capped is in valve. with standard. compliance standards regulate equipment design. For Design enclosed combustion devices must meet example, design specifications related to minimum certain times and temperatures. Equipment design residence also apply to certain pumps and specifications sampling connectors, product accumulator compressors, flares, and or types of equipment. vessels, standards regulate equipment operation. If Operational is in compliance with regulations. For example, it open-ended line or open valve that is equipped each through a negotiated rulemaking process developed was published in Federal Register on March 6, and all Such alternatives include equipment promulgated. (use, design, operation) and work standards, standards products. A complete list of affected styrene-based is presented in Appendix A. A total of 149 processes Performance Standards detectable emissions," which generally applies to =no compressors, pressure relief devices in gas/ pumps, will is a reduction efficiency of 95 percent, performance applies to several types of control devices. Vapor which Equipment Standards Types of Standards equipment standards, and 3) work practice standards. 2) most equipment, more than one type of standard is For percent reduction). For most equipment is operated in specified manner, n which performance standard can be those cases in 12

25 a second valve is to be operated in with valve on process fluid end is that second valve is closed. If open-ended valve or is operated in this manner, n it is in compliance line practice standards pertain primarily to LDAFI Work implemented by federal regulations. LDAR programs rely on monitoring of various components programs regular intervals to determine wher y at are If y are leaking, n repair part of leaking. program is instituted. Pumps and valves LDAR are covered by LDAR programs. regulations also require certain components to to determine "evidence of a leak." This monitored covers pumps and valves in heavy liquid requirement pressure relief devices in liquid service, and service, and or connectors. flanges in following discussion Addressed NSPSs are SOCMI, petroleum refining, natural gas processing, for polymer manufacturing source categories and and for benzene and vinyl chloride NESHAPs sources. distinctions between regulations (or groups Specific regulations) are noted. Readers also should refer within discussions under Sections and for to about specific source categories. information defined, primarily in and Or are might have different definitions standards might or ones in se two sections. supplement reviewed here are presented to help clarify definitions sources to which a standard applies. emission facility" definitions for four NSPS "affected of standards contain following generic All "a process unit can operate independently if definition:.with sufficient storage facilities for supplied Each standard also contains specific product." natural gas Onshore plants processing Equipment Leak Standards--Affected Facility NSPS Definitions group of all equipment within a unit process Each compressor group of all equipment within a unit process gas service VOC service or in wet group of all equipment except within a process unit compressors group of all equipment within a unit process Section for a more complete discussion of affected See faciles. natural gas Onshore plants processing (benzene NESHAP vinyl chloride) and Specific Process Unit Definition assembled to produce, Components as or final products, one or more intermediate chemicals listed in of of W. Subpart assembled for extracfion of Equipment gas liquids from field gas, natural of liquids into natural gas fractionation or or operations associated products, procasslng of natural gas with products. production of polypropylene, polystyrene (general polyethylene, crystal, or expandable), or purpose, terephthalate) or one of tr poly(ethylene derivatives as intermediates or final Its or equipment assembled to use products, Under all of standards, a process unit Note: operate can if supplied with sufficient feed independently raw materials and or sufficient storage facilities for product. clarifies definition of process unit for EPA standards, as follows: SOCMI definition was drafted by EPA to provide a way to determine which equipment is practical a manner such Table 2-3. closed before Standard Affected Facility* with standard. SOCMI Petroleum refineries Work Practice Standards A compressor in Polymer plants manufacturing be Process Unit Definitions---Specific Qualifiers Table Standards in Detail Standard SOCMI assembled to produce Components or final products from intermediate Petroleum refineries unfinished petroleum petroleum, or or intermediates. derivatives, Definitions standards Various terms that are used frequently in Polymer plants manufacturing assembled to perform any of Equipment physical and chemical operations in how standards are applied. copolymers. assembled to produce VHAP or Equipment Facility Affected affected facility is an emission source or group of An a VHAP in production of a product. leak standards are shown in Table 2-3. For equipment equipment leak standards, each individual NESHAP of equipment (e.g., pump, compressor) is piece facility. affected Process Unit an affected facility. re are no specific included in boundaries or size criteria. definition physical depends upon several operational factors, instead qualifiers (see Table 2-4). 13

26 chemical produced and configuration of including processing equipment. Such configurations may different for different producers of same be refore, definition may be fairly site chemical; In practice, however, definition will specific. selection of a process unit basis as implement "source" covered by standards (U.S. EPA, 1980). Equipment definitions are given in each of se Equipment are needed to cover different ways to equipment compressors as separate affected facilities in identify petroleum refinery and onshore natural gas plant standards and to cover exemption processing sampling connection systems in onshore natural gas of plants from equipment leak standards. processing standard contains same leak definitions. For Each a leak is detected if 1) a portable VOC pumps, natural gas Onshore plants processing (benzene NESHAP vinyl chloride) and Equipment Definitions Equipment Definition pump, compressor, pressure relief Each sampling connection system, device, valve or line, valve, and open-ended or or connector in VOC service flange any devices or systems required by and subpart.* this valve, pump, pressure relief device, Each connection system, open-ended sampling or line, and flange or or connector valve VOC service. For purposes of in and reportingonly, recordkeeping are considered equipment. compressors pump, compressor, pressure relief Each sampling connection system, device, valve or line, valve, and open-ended or or connector in VOC service flange any devices or systems required by and subpart.* this pump, pressure relief device, Each valve or line, valve, open-ended VOC service or wet gas service, and any devices or in required by this subpart.* systems pump, compressor, pressure relief Each sampling connection system, device, valve or line, valve, flange or 0Pen-ended connector, product accumulator or or systems required by this devices subpart.* phrase refers to devices or systems, such as alarms or dual This seals, that might be required to satisfi/performance or mechanical equipment standards. See Section of liquid dripping from pump seal are indications For compressors, a leak is detected if observed. indicates failure of seal system, barrier sensor or both. ( standards require each barrier system, system to be equipped with a sensor that will fluid such system failures.) For valves in gas/vapor detect service, light liquid service, or VHAP service, a if an instrument reading of >10,000 ppmv is detected For pumps and valves in heavy liquid measured. pressure relief devices in liquid service, and service, and or connectors, a leak is detected if an flanges HON rule is expected to phase in stricter leak for pumps and valves. For most pumps in definitions light liquid service, leak definition is expected to be in gas/vapor or light liquid service, leaks valves are expected to be defined as 500 ppmv. ultimately NSPS equipment leak standards apply to that are "in VOC service." definition components in SOCMI equipment leak standard is contained piece of equipment which contains or contacts a "any fluid that is at least 10 percent VOC by weight." process definition also is referenced in petroleum This 1980). NSPS equipment leak standards differ depending wher equipment in VOC service is in "gas/ on service," "light liquid service," or "heavy liquid vapor While all of NSPSs use same definition service." in light liquid service and in heavy liquid service, for natural gas processing plant standard onshore alternative definitions for both light and heavy provides service. petroleum refinery and vinyl chloride liquid also provide an alternative definition for in standards light liquid service. NESHAP equipment leak standards apply to A VHAP is defined in 40 CFR Part 61, Subpart VHAPs. as "... a substance regulated under this part for V a standard for equipment leaks of substance which limited exception to this rule ( 60,562-2) applicable to 1Note pumps used in polymer manufacturing industry. This certain exemption is discussed in Section leak is standards (see Table 2-5). instrument reading of >10,000 ppmv is measured. Different definitions of from 10,000 ppmv to 1,000 ppmv within 2Y2 reduced following date of applicable rule. For years Leak Definitions VOC Service In instrument reading of >10,000 ppmv is measured, or 2) Table 2-5. Standard SOCMI onshore natural gas processing, and polymer refinery, equipment leak standards. 10 manufacturing VOC cutoff was selected by EPA to avoid percent those sources that have only small amounts of covering equipment (U.S. EPA, ozone forming substances in Petroleum refineries Polymer plants manufacturing VHAP Service In compressor, and flange in has been proposed and promulgated." Under vessel in VHAP service, and any control 14

27 VHAP service" means that a piece of equipment "In contains or contacts a fluid (liquid or gas) that is eir least 10 percent by weight a VHAP. This is same at definition for "in benzene service" found in basic equipment leak standard (40 CFR Part 61, benzene J). Subpart vinyl chloride, "in vinyl chloride service" means that For piece of equipment eir contains or contacts a liquid a at least 10 percent vinyl chloride by weight or a definition, rar than "in VHAP service" This found in Subpart V, is used in vinyl definition standards (40CFR Part 61, Subpart F) for chloride applicability of Subpart F. determining gas/vapor service" means, that piece of "In contains process fluid that is in gaseous equipment at operating conditions. Each of four NSPS state uses this definition. Subpart V defines "in Standards is "in light liquid service" if both of Equipment conditions apply: following vapor pressure of one or more components is kpa (0.04 psi) at 20 C. >0.3 total concentration of pure components, with vapor pressure >0.3 kpa (0.04 psi) at 20 C, is >20 a by weight, and fluid is a liquid at percent conditions. operating addition, to above definition, petroleum In onshore natural gas processing, and polymer refinery, plant standards allow an owner or manufacturing to define equipment as in light liquid service if operator percent evaporated is greater than 10 percent at as determined by ASTM Method D C, heavy liquid service" means that piece of "In is neir in gas/vapor service nor in light equipment service if weight percent evaporated is <10 liquid at 150 C, as determined by ASTM Method percent Although not explicitly stated in petroleum D-86. standard, this alternative definition also can be refinery V defines "in liquid service" rar than Subpart between "in light liquid service" and "in differentiating liquid service." In liquid service means that a heavy of equipment is not in gas/vapor service. piece se definitions are incorporated by reference in While J (benzene), Subpart F (vinyl chloride) does Subpart differentiate between in gas/vapor service and in not service. Components "in vinyl chloride service" liquid covered in same manner regardless of fluid are state. and Flanges Connectors and or connectors are one group of Flanges components covered by equipment leak equipment In 40 CFR Part 60, Subpart VV, connectors standards. defined as fflanged, screwed, welded, or or are fittings used to connect two pipe lines or a pipe joined to equipment in VHAP service) is expanded by only statement, added on September 30, 1986 (51 following 34915): "For purpose of reporting and FR connector means flanged fittings that recordkeeping, not covered by insulation or or materials that are location of fittings." prevent "product accumulator vessel" is any distillate A bottoms receiver, surge control vessel, or receiver, separator in VHAP service'that is vented to product eir directly or through a vacuum- atmosphere and only Subpart J, Part 61 regulates product vessel, vessels. A number of questions have been accumulator by regulated industry about application of raised definition, and some clarification is presented in this Leak Detection and Repair programs consist of two phases: 1) LDAR fugitive emission sources within a process unit potential detect VOC leaks, and 2) repair or replacement of to component. level of emission reduction leaking by an LDAR program is affected by several achieved three main factors are monitoring interval, factors. definition, and repair interval: leak Monitoring interval-- monitoring interval is at which individual component monitoring frequency In Liquid Service HON for organic chemical manufacturing proposed 149 substances will be defined as VHAPs. facilities, that is gas that is at least 10 percent vinyl chloride by volume. In Gas Service line and a piece of process equipment." Subpart V (40 CFR Part 61), this definition (applicable In service" same as it defines NSPS gas/vapor leak standards. equipment In Light Liquid Service Product Accumulator Vessels producing system. A product accumulator vessel is in liquid or vapor in vessel is at VHAP service if least 10 percent by weight a VHAP. Only Subpart V, Part 61 defines product accumulator Section 3.8 of this handbook. In Heavy Liquid Service monitoring service. onshore natural gas processing liquid standard also defines equipment as in heavy plant used for equipment located at petroleum refineries. 15

28 conducted. Pumps and valves are to be monitored is a month. For valves, monitoring interval once be extended to once every quarter for each may that has not leaked for 2 successive months. valve pumps, LDAR program also specifies a For visual inspection for indications of liquids weekly (or VHAP) concentration observed during VOC that defines leaking sources. Two primary monitoring affect selection of leak definition: 1) factors percent total mass emissions that potentially can controlled by LDAR program, and 2) ability be repair leaking components. Under current to leak definition employed for leak standards, monitoring is 10,000 ppmv. detection Repair interval-- repair interval is defined as of time allowed between detection of a leak length repair of leak. When a leak is detected, and component is required to be repaired as affected days after leak is under "Delay of Repair" (later in this described are met. section) For each component, first attempt at repair is to made no later than 5 calendar days after each be is detected. For valves, first attempts at repair leak but are. not limited to, following best include, where practicable: practices, of bonnet bolts Tightening of lubricant into lubricated packing Injection standards do not identify similar first attempt practices for or components. repair factors could improve efficiency of an Or program, but are not addressed by LDAR se factors include training programs standards. equipment monitoring personnel and tracking for that address cost efficiency of systems equipment (i.e., competing brands of alternative in a specific application). valves programs affect valves and pumps and or LDAR Each of se components will be components. LDAR Programs Valve categories of valves to which monitoring Four valves covered by NESHAP standards (40 CFR For 61, Subpart V), only three valve categories are Part equivalent to standards. only difference is that first NSPS for NESHAPs does not distinguish between category and light liquid service; it is simply "in VHAP gas/vapor service." LDAR programs are discussed in following Valve for each of first three categories. After one section of monitoring is completed, alternative standards year available for valves in gas/vapor, light liquid, or are service. A discussion of valves in heavy liquid VHAP is presented in section called "Or service LDAR Programs." Equipment in Gas or Light Liquid Service and Valves Valves VHAP Service. Monthly monitoring is required for in in gas/vapor or light liquid service and valves in valves selecting monitoring interval, EPA frequent monitoring would allow leaks to be more earlier, thus allowing more immediate repair." detected considered monitoring intervals of less than 1 EPA for se valves, but noted that large number month valves in certain SOCMI process units limits of minimum for monitoring intervals. For practical time is required to schedule repair after a leak is some monitoring intervals of less than month detected, result in a situation in which a detected leak could could be repaired before next required monitoring. not also considered a number of longer monitoring EPA including annual, semiannual, quarterly, and intervals, with monthly followup on leaking valves. quarterly intervals, along with monthly monitoring, were se for cost effectiveness and emissions compared achievable. Based on analysis of reductions of monitoring interval on costs and emissions effect EPA selected a monthly monitoring program reduction, that monthly monitoring does have determined cost effectiveness and reasonable reasonable cost effectiveness. FLrrmore, monthly incremental yields largest emissions reductions of all monitoring examined programs. Valves in gas/vapor or light liquid service Valves demonstrated to be difficult-to-monitor Valves demonstrated to be unsafe-to-monitor Valves in heavy liquid service from pump seal. dripping Leak definition-- leak definition is specified first three categories listed above for 15 calendar soon as practicable, but not later than detected, unless conditions VHAP service. In that, in general: "... more frequent monitoring noted result in greater emissions reductions because would of bonnet bolts Replacement of packing gland nuts Tightening large process units, a two-person team could typical more than 1 week to monitor all valves. Since take se SOCMI standards. While less frequent for were found to be more cost effective, EPA programs discussed in greater detail in following sections. apply are listed in 40 CFR Part 60, requirements VV: Subpart 16

29 National Air Pollution Control Techniques At Committee meeting (a public hearing held Advisory and manpower inefficiently. If this is correct, time effort should be increased in proportion to monitoring frequency with which valves leak. Eor any that do not leak for 2 successive months, valves standards allow an owner or operator to refore, such valves from monitoring until first exclude of next quarter. reafter, such valves can month monitored once every quarter until a leak is be again has been shown to leak free for 2 successive months. At such time, be monitoring may be resumed. quarterly Standards. In an effort to provide flexible Alternative EPA included two alternative standards for standards, gas/vapor or light liquid service and valves in service. Owners or operators of affected facilities VHAP allowed to select and comply with eir of are standards instead of monthly monitoring alternative program, allowing m to tailor equipment leak LDAR for se valves to ir own operations. requirements and operators are required first to implement a Owners monthly monitoring program for at least 1 year. n, a during 1 year of monthly monitoring. gared first alternative standard for se valves limits percent of valves leaking within a process maximum to 2.0 percent, to be determined by a minimum of unit annual performance test. This alternative was one to eliminate unreasonable costs; it provides provided incentive to maintain good performance levels while an low-leak unit design. standard can be promoting by implementing any type of LDAR or engineering met program chosen by owner or operator. control compliance-demonstrating performance test is A initially upon designation, annually, and at required times, as requested by Administrator. or tests are to be conducted by monitoring, Performance week, all valves in gas/vapor and light liquid within or all valves in VHAP service located in service facility. An instrument reading of >10,000 ppmv affected a leak. leak percentage is calculated by indicates number of valves for which leaks dividing are by total number of valves in gas/vapor and detected liquid service or in VHAP service within light unit. Inaccessible valves that cannot be process on a routine basis are included in monitored test and subsequent annual tests. performance monitoring interval is not considered annual for such valves. If performance results burdensome more than 2.0 percent valve leakage, process show is not in compliance with alternative standard. 2 unit and operators electing to comply with this Owners standard are required to notify alternative 90 days prior to implementation. If Administrator or operators determine that y no longer wish owners comply with this alternative standard, y can submit to wdtten notification to Administrator, affirming a LDAR program. Under skip-period skip-period detection provisions, an owner or operator can leak from routine monitoring (monthly) to less skip monitoring after completing a number of frequent better than 90 percent certainty that all periods and this performance level, following sets of have After two consecutive quarterly periods with of leaking valves <2.0, owner or. percentage may skip to semiannual monitoring. operator After five consecutive quarterly periods with alternative requires that, if percentage of This leaking is >2.0, monthly LDAR program valves in or , as appropriate, specified be reinstated. Reinstituting monthly LDAR must not preclude an owner or operator from electing to does alternative standard again. use with first alternative standard, owners and As electing to comply with second operators standard must notify Administrator 90 alternative before implementation. In addition, owners or days because access is restricted. standards monitor an annual LDAR program for valves that are allow to monitor. Valves that are difficult to monitor are difficult as valves that would require monitoring defined this alternative, failing a performance test results in immediate Under 2.0 percent monitoring alternative is only situation violation. which leak detection monitoring can result in a violation. In all in cases, a violation does not occur as a result of monitoring. or occur only if first attempt at repair is not made within 5 Violations or final repair is not completed within 15 days after leak days development of standards), industry during argued that, because some valves leak representatives or significantly less often than ors, infrequently all valves on a monthly basis would expend monitoring with work practice standard in compliance as appropriate. 7, second alternative standard for se valves is a detected. If a valve leak is detected, monthly monitoring of that valve is required until it sequential monitoring intervals. Considering successful performance level of less than 2.0 percent leakage a valves in conservative periods and fractions of were established: periods skipped owner or operator can elect to comply with one of plant alternative standards based on information of leaking valves <2.0, owner or percentage may skip to annual monitoring. operator must identify with which of two skip operators y are electing to comply. periods Some valves are difficult to Difficult-to-Monitor Valves. is detected. 17

30 to ensure that ladders are used to elevate intended personnel under safe conditions. Valves that monitoring ladders are as difficult-to-monitor and may be monitored classified rar than monthly. annually valves are limited in new process Difficult-to-monitor In new NSPS units, up to 3 percent of valves units. be designated as difficult-to-monitor; existing can process units can have more than 3 percent NSPS valves. NESHAP standards difficult-to-monitor difficult-to-monitor valves in existing process units allow Valves. Some valves are classified Unsafe-to-Monitor "unsafe-to-monitor." Unsafe-to-monitor valves cannot as eliminated in new or existing units. standards be an owner or operator to submit a plan that defines allow LDAR program conforming as much as possible with an routine monitoring requirements of standards, that monitoring should not occur under unsafe given Unsafe-to-monitor valves are defined as conditions. valves that could, based on judgment of those or operator, expose monitoring personnel to owner hazards from temperature, pressure, or imminent process conditions. explosive LDAR Programs Pump monitoring is required for pumps in light liquid Monthly or in VHAP service (unless an owner or service elects to comply with equipment design operator seals with controlled degassing vents. Both mechanical programs are less costly than equipment LDAR lowest average and incremental costs installation. megagram of reduced VOCs were associated with per monthly LDAR program. monthly LDAR achieves greater emissions reductions than program quarterly LDAR program, but less than of control equipment. Because installation costs for equipment were considered to incremental unreasonably high relative to resulting be emissions reductions, EPA selected incremental monitoring as basis for standards. monthly pump in light liquid or VHAP service is to be Each by visual inspection each calendar week for checked of liquid dripping from pump seal. indications LDAR requirements contain an additional NESHAP whereby any pump located within provision of an unmanned plant site is exempt from boundary of Repair Delay recognizes that repair of leaking components EPA need to be delayed for technical reasons. Both 40 might Part 60, Subpart VV, and 40 CFR Part 61, Subpart CFR identify following circumstances under which V, may be delayed: repairs Delay of repair of leaking equipment is allowed if is technically infeasible without a process unit repair An example of such a situation would be a shutdown. valve that could not be isolated from leaking stream and that would require complete process or replacement of internal parts. When replacement valve cannot be physically isolated from a stream, process unit must be shut down process repair valve. Thus, because EPA believes that to shutdown of a process unit to repair mandating that are infeasible without a Delay of repair is allowed for equipment that is from process and does not remain in isolated or VHAP service. This typically applies to spare VOC that is out of service. Delay of repair is not equipment hqwever, for spare eluipment that is allowed, and prepared to be placed on-line; such pressurized Delay of repair for valves is allowed if emissions purged material resulting from immediate of are greater than fugitive emissions likely to repair from delay. Delay also is allowed if, during result recovered in a control device complying with or or , as applicable of repair beyond a process unit shutdown is Delay for valves if following conditions are allowed assembly supplies have been depleted. Valve assembly supplies had been stocked Valve before supplies were depleted. sufficiently of repair beyond next process unit Delay occurs sooner than 6 months after first shutdown unit shutdown. process Delay of repair for pumps is allowed if use of a dual mechanical seal system that a barrier fluid system, and if repair is includes to be elevated more than 2 meters above any personnel available support surface. This definition is permanent cannot be safely monitored by use of but not in new process units. unreasonable, EPA allows delay of repairs valves is shutdown. is still considered to be in VOC or VHAP equipment service. repair, purged material is collected and destroyed EPA examined monthly and quarterly standards). LDAR programs and use of dual monitoring met: necessary during Valve assembly replacement is process unit shutdown. shutdown is not allowed unless next process unit repairs require.visual inspection requirements, provided that weekly pump is inspected visually as often as practicable each as soon as practicable, but not later than completed months after leak is detected. 6 and at least monthly. 18

31 CFR Part 61, Subpart F (vinyl chloride), with 40 differences: following A reliable and accurate vinyl chloride monitoring shall be operated for detection of major leaks system identification of general area of plant and a leak is located. where monthly monitoring requirements for valves are applicable to any process unit in which not in part, on monitoring of a minimum of based, valves or 90 percent of total valves in a 200 Equipment LDAR Programs Or and valves in heavy liquid service, pressure Pumps light liquid or heavy liquid service, and and or connectors are to be monitored within flanges days if evidence of a potential leak is found by visual, 5 olfactory, or any or detection method. A audible, of >10,000 ppmv indicates a leak. se reading pressure relief devices in gas/vapor service, For natural gas processing plant standard allows onshore owner or operator to monitor se components on a an basis to determine wher a leak exists. A quarterly of >10,000 ppmv indicates a leak. This differs reading Subpart VV, which requires se components to from operated with "no detectable emissions." ( be is due to results of cost and emission difference onshore natural gas processing plants.) Both at require monitoring of pressure relief devices subparts natural gas processing plant NSPS also provides after a pressure release in a nonfractionating plant that only by nonplant personnel, pressure relief monitored may be monitored next time personnel are devices site (instead of within 5 days noted above). on components, however, must be monitored within se from LDAR Programs Exemptions natural gas processing plants, pumps in For valves in gas/vapor service, valves in light service, service, and pressure relief devices in gas/vapor liquid are exempt from routine LDAR requirements service (a)(1), (a), and (b)(1) if of y are located 1) at a nonfractionating plant with a capacity to process <10 million scfd of field gas, design 2) in process units in Alaskan North Slope. or petroleum refineries, pumps in light liquid service For valves in gas/vapor and light liquid service within a and unit that is located in Alaskan North Slope process exempt from routine LDAR requirements of are Equipment, Design, Operational, and Standards Performance section is focused on equipment, design, This and performance standards. Equipment operational, refer to use of specific types of standards Design standards include requirements components. dual mechanical seals, closed purge and vent for caps, blind flanges, second valves, and systems, equipment specifications associated with flares control enclosed combustion devices. and equipment operations, e.g., proper sequence Certain closing double blocks and bleed valves or for to maintain a pilot flame in flares, are requirement through implementing operational standards. regulated Performance standards refer to percent reduction efficiency for control devices. and monitoring is used for components subject to Annual "no detectable emissions" requirement, which emissions of less than 500 ppmv above requires s for both NSPSs and NESHAPs. se system are to be tested for compliance with no components emissions initially upon designation, detectable and at or times, as requested by annually, monitoring intervals are specified in NSPS Or NESHAP rules for pressure relief devices in gas/ and service. y are to be monitored as soon as vapor but no later than 5 calendar days after a practicable, release, to determine wher device has pressure returned to a condition of no detectable emissions. been or performance standard applies if One percentage of valves leaking" alternative "allowable has been elected. In that case, standard standard allows not more than 2.0 percent performance Pumps addition to LDAR program, regulations In same LDAR requirements as identified in 40 CFR for like components are adopted in Part 61, Subpart V, and of leaking valves is demonstrated to be percentage than 2.0. calculation of this percentage is less process unit, whichever is less. relief devices in no detectable emissions also apply to NESHAP pressure relief requirements in liquid service and flanges and or devices connectors. levels. No detectable emissions components background pumps, compressors, valves (specifically include for no detectable emissions), pressure designated devices in gas/vapor service, and closed-vent relief reduction analyses for emission reduction alternatives Administrator. within 5 days after each pressure release. 30 days after a pressure release. valves. Performance tests must be conducted leaking annually, and at or times, as requested by initially, light liquid Administrator. identify equipment, design, operational, and performance 19

32 for pumps. regulations state that a pump standards not need to comply with LDAR program if it does Mechanical Seal System. A pump in light liquid Dual is exempt from LDAR program if it is service with a dual mechanical seal system that equipped a barrier fluid system. (This does not exempt includes pumps from weekly visual inspection for such of liquid dripping from pump seals.) indications Operated with barrier fluid at a system must pressure that at all times greater than pump stuffing is or pressure; Equipped with a is connected by a closed vent system to a that device; or control emissions to atmosphere. VHAP) barrier fluid system is to be eir in heavy liquid fluid system, or both. owner/operator can barrier criterion to be used to indicate failure. determine Each pump is to be checked by visual inspection calendar week for indications of liquids dripping each Each sensor is to be checked daily or is to be with an audible alarm. equipped as soon as practicable, but no later than 15 repaired after it is detected, except as provided by days "Delay of to take place no later than 5 days after a leak is is detected. Detectable Emissions. A pump does not need to No with LDAR program or dual mechanical seal comply so designed can be designated for no Pumps emissions if y are 1) demonstrated to be detectable with no detectable emissions as indicated by operating instrument reading of less than 500 ppmv above an 500 ppmv above background reading initially upon than designation, annually, and at or times as its with a closed-vent system capable of equipped and transporting any leakage from seal or capturing to a control device that complies with seals identified in rule for such a control requirements it is exempt from requirements identified in device, preceding paragraphs. Pumps in light liquid service located in Exemptions. process units in Alaskan North Slope are affected by Subparts GGG and KKK, from routine exempt, requirements, but are not exempt from LDAR plants with a design capacity of less nonfractionating 10 million scfd, are exempt from routine LDAR than (but not from equipment standards) under requirements KKK. Subpart Compressors basic requirements for compressors are found in of Subpart VV (40 CFR Part 60) and of Subpart V (40 CFR Par 61). Compressors barrier fluid system and that prevents leakage of a to atmosphere, or 2) a closed-vent system VOCs control device. performance standard is for no and emissions. se standards are discussed detectable System with Barrier Fluid System. regulations Seal each compressor seal system to meet require following criteria: Operated with barrier fluid at a pressure that greater than compressor stuffing box is or pressure; with a barrier fluid system that is Equipped by a closed-vent system to a control connected into a process stream with zero VOC (or fluid emissions to atmosphere. VHAP) barrier fluid system is to be eir in heavy liquid or not in VOC service. service one of or standards, which are discussed meets following section. in by Administrator. requested System and Control Device. If a pump is Closed-Vent To be exempt from LDAR program, pumps with a dual mechanical seal system/barrier fluid of following six conditions: meet all Each dual mechanical seal system must be: standards. equipment in light liquid service, located in any Pumps barrier fluid degassing reservoir with a system that purges barrier Equipped into a process stream with zero VOC (or fluid comply with eir an equipment design standard may a performance standard. equipment design or service or not in VOC service. Each barrier fluid system is to be equipped with a that will detect failure of seal system, sensor standard requires eir 1) a seal system that includes in following section. from pump seals. Each system must be: When a leak is detected (eir by visual inspection by sensor indicating a failure),.it is to be or Repair" provisions. A first attempt at repair or device; with a system that purges barrier Equipped requirement if it does not have an externally system shaft that penetrates pump housing. actuated Each barrier fluid system is to be. equipped with a that will detect failure of seal system, sensor background, and 2) tested for compliance with less barrier fluid system, or both. regulations allow 2O

33 owner/operator to determine criterion to be to indicate failure. used Each sensor is to be checked daily or is to be with an audible alarm. equipped standards for compressors do not require weekly inspection for indications of a potential leak as is visual required for pumps in not need to comply with equipment design does if it is equipped with a closed-vent system that standard capable of capturing and transporting any leakage is seal to a control device. control device from comply with requirements specified in must for that control device. rules Detectable Emissions. Compressors that may be No for "no detectable emissions" do not need designated comply with eir equipment design standard to Compressors that are designated for no described. for compressors if only means for standards compressor into compliance with bringing Subpart GGG also has an exemption for compressor. in hydrogen service. Subpart KKK compressors exempts reciprocating compressors in reciprocating compressors are covered. and requirements for compressors in VHAP monitoring under NSPS standards, with one exception. service located within boundary of an Compressors need to be checked daily or equipped with an not alarm. audible eir to operate with no detectable required performance standard--or to be equipped emissions--a a closed-vent system and control device--a with standard. For pumps and compressors, no design emissions refers to an instrument reading of detectable than 500 ppmv above background. Pressure relief less complying with no detectable emissions devices are to be returned to that condition within 5 standard days after each pressure release, except as calendar in "Delay of Repair" provisions. provided device no later than 5 calendar days after a relief release to confirm that no detectable emissions pressure pressure relief devices need not comply with no emissions standard if y are equipped detectable closed-vent systems capable of capturing and with leakage from pressure relief device to transporting control device that meets requirements for that a device. control Connection Systems Sampling connection systems are to Sampling closed-purge system or a closed-vent system. Each a system or closed-vent system should do closed-purge line with zero VOC (or VHAP) emissions to process atmosphere. Collect and recycle purged process fluid with VOC (or VHAP) emissions. zero Capture and transport all purged process fluid to control device that complies with requirements a valves or lines only have equipment open-ended including operational requirements; no standards flange, plug, or second valve to seal open end blind all times, except during operations requiring process at Pressure Relief Devices in Service Gas relief devices in gas/vapor service are Pressure When a leak is detected (eir by visual inspection by sensor indicating a failure), it is to be or as soon as practicable, but no later than 15 repaired after it is detected, except as provided by days of Repair" provisions. A first attempt at repair "Delay to take place no later than 5 days after a leak is is detected. liquid service. light System and Control Device. A compressor Closed-Vent pressure standards also require monitoring of has been achieved. emissions are to comply with this performance detectable by a demonstration, that y are operating standard be equipped with no detectable emissions, as indicated by a less with 500 ppmv above background instrument reading. than of following: one Return purged process fluid directly into required initially upon designation, This demonstration is reafter, and at or times as requested by annually Administrator. Both Subparts VV and GGG exempt Exemptions. compressors from equipment reciprocating through (e)and (h) involves eir recasting of 3(a) distance piece or replacement of for that control device. wet gas service VV, GGG, V, and J exempt in situ sampling Subparts and Subpart KKK exempts all sampling systems, all of , but requires reciprocating from in NGL service to comply with compressors connection systems. V, F, and J (40 CFR Part 61) do not exclude Subparts type of compressor from compliance; both rotating any Valves or Lines Open-ended to sampling connection systems standards, Similar service are same as those for compressors in VOC or work practice standards apply. Open- performance valves or lines must be equipped with a cap, ended unmanned plant site must have a sensor, but se do fluid flow through open-ended valve or line. 21

34 a second valve is used, open-ended line or valve If to be.operated so that valve on process fluid is is closed before second valve is closed. If a end block-and-bleed system is being used, double valve or line may remain open during operations bleed require venting line between block valves. that fluid flow through open-ended line or process valve). programs are primary standards for controlling LDAR leak emissions from process valves. equipment also allow, however, use of an regulations design standard for valves. A valve that is equipment so that no external actuating mechanism designed in contact with process fluid may be comes to comply with performance standard of designated detectable emissions. As with or equipment no designated, valves designated for no detectable so must be operated with emissions less than emissions ppmv above background and must be tested for 500 with less than 500 ppmv above compliance reading initially upon designation, annually background and at or times as requested by reafter, Valves that meet equipment design Administrator. include weir diaphragm valves, bonnet standard of a potential leak" work practice standard evidence in Section No equipment or discussed vessels (NESHAP only) are subject to se standards only; performance or work equipment with a closed-vent system capable of equipped and transporting any leakage from vessel capturing a control device that meets requirements for that to device. control Agitators agitators in vinyl chloride service are required to All double mechanical seals, or an equivalent have installed to minimize vinyl chloride mechanism, from seals. If double mechanical seals are emissions one of following is required: 1) maintaining used, pressure between two seals so that any leak occurs is into agitated vessel; 2) ducting any that chloride between two seals through a control vinyl from which vinyl chloride in exhaust system does not exceed 10 ppmv; or 3) an equivalent of gases with individual equipment components, As systems and control devices that can be closed-vent to comply with standards also have design, used and performance standards. operation, Systems. Closed-vent systems are to be Closed-Vent for and operated with no detectable designed y are to be monitored at start-up, emissions. reafter, and at or times as requested by annually addition, closed-vent systems are be operated at all times when emissions might be to to m. vented Regulated control devices are vapor systems, enclosed combustion devices, and recovery Control devices are to be monitored to ensure flares. maintenance and operation. parameters to proper monitored are selected by plant owner or be regulations also require that control operator. are operated at all times when emissions might devices recovery systems (such.as condensers and Vapor are to be designed and operated to recover, adsorbers) an efficiency of >95 percent, organic vapors with to m. vented combustion devices are required eir to Enclosed organic emissions by at least 95 percent or to reduce operated with a minimum residence time at a be temperature. For enclosed combustion minimum used to comply with NSPSs, minimum devices time is 0.75 seconds and minimum residence is 816 C. For enclosed combustion temperature used to comply with NESHAPs, se values devices 0.5 seconds and 760 C, respectively. are in residence times and temperatures differences in part, continuing research and conclusions as reflect, minimum residence time and temperature to are to comply with requirements of subpart V incorporates se same provisions. use Subpart a steam-assisted, air-assisted, or nonassisted flare of required by se flares are to be operated is no visible emissions, except for periods not to with a total of 5 minutes during any 2 consecutive exceed y are to be operated with a flame present at hours. times. presence of a flare pilot flame is to be all such measures mentioned in 1) and 2). all or times, open end of bleed valve or line At be sealed (except during operations requiring must Closed-Vent Systems and Control Devices Process Valves Administrator. In Control Devices. be vented to m. diaphragm seal valves, and sealed bellows valves. and Or Connectors Flanges and or connectors are subject to "no Flanges standards are available for se performance components. Product Accumulator Vessels standards do not apply. equipment practice require product accumulator vessels to be standards to achieve >95 percent reduction efficiencies. required stated in Subpart W, flares used to comply with that As monitored using a rmocouple or any or equivalent 22

35 to detect presence of device flame. In addition, a or operators are to monitor flares to ensure owners that y are operated and maintained in maximum exit velocities for flares and identified are in 2.2.4,4 Equivalent Means of Emission Limitations standards, any owner Under operator of an or facility can request that Administrator affected equivalence of any alternative determine means emission limitation to equipment, design, of and work practice requirements of operational, standards for pressure relief devices in standards. service and standards for delay of repair, gas/vapor are excluded from this provision. however, means of emission limitations equivalent same are both NSPSs ( ) and NESHAPs ( ). for owner or operator subject to provisions of Each leak regulations may apply to equipment for determination of equivalence for any Administrator of emission limitation that achieves a reduction means VOC or VHAP emissions that is at least equivalent to VOC/VHAP emissions achieved by required in regulations. In addition, controls of equipment used to control equipment manufacturers of VOCs/VHAPs can apply to Administrator leaks determination of equivalence for any means of for that achieves a reduction in VOC/VHAP limitation achieved by equipment, design, and emissions requirements of regulations. operational receiving a request for determination of After Register. If Administrator judges that Federal might be approved, an opportunity for a public request is provided. After notice has been published hearing opportunity for a public hearing has been and is published in Federal Register. Any approved n means of emission limitation constitutes equivalent a of Clean Air Act. Guidelines used to for equipment, design, and operational determination are as follows: requirements equivalence of means of emission demonstrate Sufficient information needs to be limitation. demonstrate that alternative control Administrator compares test data submitted owner, operator, or equipment manufacturer by test data for equipment, design, and to requirements. operational Administrator is allowed to condition of equivalence on requirements that might approval necessary to ensure operation and maintenance be achieve same emission reduction as to design, and operational requirements. equipment, following guidelines are specified for determining with required work practices: equivalency Each owner or operator is responsible for collecting For each affected facility for which a determination of is requested, emission reduction equivalence by required work practice first must be achieved NESHAP regulations require demonstrated. period to be at least 12 months, and demonstration regulations do not have a minimum NSPS Each owner or operator is to commit, in writing, to practice(s) that provide for emission reductions work limitation to demonstrated emission emission for required work practice and will reduction commitment of owner or operator to consider alternative work practices. Administrator may condition approval of on requirements that might be necessary equivalence ensure operation and maintenance to achieve to emission reduction as required work same practice. y desire, owners or operators may offer a unique If requirements associated with test methods and used to comply with standards are procedures in this section. Each owner or operator is outlined to comply with test methods and required requirements provided in specified procedural of regulations. sections conformance with ir designs. Finally, minimum net heating values and verifying test data to demonstrate equivalence of means of emission limitation. time period. demonstration For each affected facility for which a determination of in reduction in is requested, emission reduction equivalence by alternative means of emission achieved limitation also must be demonstrated. to or greater than emission reductions equal by required work practice. achieved Administrator will compare demonstrated reduction for alternative means of emission equivalence, Administrator publishes a notice in Administrator determines equivalence provided, means of emission limitation. determination of work practice, equipment, design, or operational required within meaning of Section 111(h)(1) standard make this to demonstrate any equivalent means of approach limitation. emission Each owner, operator, or equipment manufacturer is for collecting and verifying test data to responsible Test Methods and Procedures collected to is equivalent to control technique technique in standards. specified 23

36 with EPA Reference Method 21. Specifics accordance Method 21 are discussed in Chapter 4. of (or VHAP) Service Presumption VOC of basic presumptions of equipment leak One is that a piece of equipment is in VOC (or standards service and, thus, is subject to standards. VHAP) presumption can be overcome by an owner or This demonstrating that piece of equipment is operator be considered not in VOC (or VHAP) service, to VOC (or VHAP) must be reasonably expected percent percent determination is to conform to weight methods described in ASTM E-260, E-168, or general of equipment is considered in wet gas service if it piece or contacts field gas before extraction contains in process. An owner or operator must step orwise to exclude equipmen t from demonstrate presumption. in-wet-gas-service determining weight percent VOC in process In an owner or operator may exclude nonreactive fluid, compounds from total quantity of organics organic that 1) substances excluded are those provided by Administrator to have negligible considered and 2) owner or operator demonstrates reactivity; percent organic content, excluding nonreactive that compounds, reasonably can be expected organic to exceed 10 percent by weight. never using procedures outlined, an owner or may elect to use engineering judgment to operator that weight percent does not exceed demonstrate disagreement. resolve an owner or operator determines that a piece of If is in VOC (or VHAP) service, equipment can be revised only after following determination rule (Subpart IV), conditions for determining a piece of equipment is in light liquid service wher vapor pressure of one or more of must be >0.3 kpa at 20 C. components total concentration of pure components with vapor pressure >0.3 kpa at 20 C is >20 percent by a weight. fluid must be liquid at operating conditions. making determination, vapor pressures may be from standard references or determined by obtained D ASTM noted earlier, Subparts KKK and GGG allow owners As operators to use an alternative definition for in light or service. In se two standards, a piece of liquid can be designated as being in light liquid equipment if weight percent evaporated is >10 percent service 150 C (as determined by ASTM Method D-86). at Samples Representative samples to be representative of process fluid For combusted in a flare, y must be taken in being with: conjunction Determining that a piece of equipment is not in VOC VHAP) service. (or Determining wher a piece of equipment is in light service. liquid requirements associated with use of flares Certain identified in Subpart VV (40 CFR Part 60) and are with visible emission provisions for compliance and monitoring of a flare pilot flame using a flares rmocouple or any or equivalent device to presence of a flame. requirements also include and sampling procedures for determining calculation heat content and exit velocity. All of se. also are found in of 40 CFR requirements Method Monitoring monitoring for leaks is to be performed in All methods of procedure; engineering judgment ASTM be used to revise determination. cannot In Light Liquid Service Conditions distinguish between equipment according to NSPSs characteristics of process fluid. In this section of In are identified: VOC (or VHAP) service. For a piece of equipment not in never to exceed 10 percent by weight. For VOCs, For VHAPs, weight percent determination is E-169. conform to general method described in to In ASTM D KKK extends this presumption to equipment in Subpart gas service (i.e., each piece of equipment is wet presumed to be in VOC service or in wet gas service). A contained in or contacting equipment or of gas Determining heat content of flare gas. Instead of Flares percent. As stated in rule, engineering 10 must demonstrate that VOC (or VHAP) judgment clearly does not exceed 10 percent by weight. If content and an owner or operator disagree about wher EPA V (40 CFR Part 61). se requirements include Subpart use of Reference Method 22 to determine engineering judgment clearly demonstrates this, appropriate ASTM method must be used to n detect Part

37 and reporting requirements are included Recordkeeping regulations to provide documentation for assessing in records and reports provide information for se personnel to assess compliance with enforcement in Table 2-6 are some of records that must Listed kept by plant owner/operator to comply with be standards; listed in Table 2-7 are some of an owner/operator is required to submit. reports of submitted reports reduces, but does not Review eliminate, required in-plant inspections. necessarily discussion of specific recordkeeping/reporting Detailed is found in Chapter 5 of this handbook. requirements Equipment IDs List test Compliance valves Unsafe-to-monitor results LDAR Monitoring NSPS of construction Notification semiannual report Initial reports Semiannual NESHAP statement Initial report Semiannual chloride--no report if fewer than 2 percent of valves Vinyl Clean Air Act Amendments of 1977 require each containing areas in which NAAQS for ozone state exceeded to adopt and submit a revised SIP to was by January 1, States that were unable to EPA attainment with NAAQS for ozone by demonstrate statutory deadline of December 31, 1982, could extensions for attainment of standard. request granted such an extension were required to States a furr revised SIP by July 1, new submit for compliance with ozone standard was deadline 172(a)(2) and.(b)(3) of 1977 Clean Air Act Section nonattainment area SIPs to include RACT required for stationary sources. EPA allowed requirements to defer adoption of RACT regulations on a states category of stationary sources of VOCs until a CTG for that VOC source category (44 FR published 44 FR ). This delay allowed states to 20372; more technically sound decisions regarding make of RACT. To date, EPA has published application documents addressing equipment leaks of guidance from petroleum refinery equipment (U.S. EPA, VOCs gas/gasoline processing plants (U.S. EPA, natural 1983b). a review of existing information and data on Although technology and cost of various control techniques to emissions is included in CTG documents, se reduce are necessarily general in nature and do not documents account for variations within a stationary source fully purpose of CTG documents is to provide category. and local air pollution control agencies with an state information base for proceeding with ir own initial of RACT for specific stationary sources. assessment CAAA have expanded significantly scope of efforts required for inclusion in SIPs. Most control nonattainment areas now are grouped into one of ozone principal classifications based on severity of five At a minimum, those states that contain ozone problem. areas are required to continue nonattainment and implementation of RACT for development sources (including equipment leaks of stationary For most states, CAAA contain a variety of VOCs). of 1994, 15 states have some form of equipment leak As in place (Alabama, California, Connecticut, regulation Pennsylvania, Texas, and West Virginia), Oklahoma, six states have programs under development or and Note: States that developed programs in 1988). or 1988 may not be included in this listing. In 1987 cases, state programs closely follow federal most regulations for equipment definition, standards, NSPS and repair requirements. Principal variations monitoring, types of sources regulated, cutoffs and are allowable test methods, recordkeeping, and exemptions, details. reporting scope of existing state regulations and of new regulations can be expected to application Recordkeeping and Reporting Requirements December 31, with each standard (work practice, compliance or equipment). Review and inspection of performance, after EPA standards. syntic organic chemical and polymer 1978); equipment (U.S. EPA, 1984a); and manufacturing Recordkeeping Requirements Table 2-6. Difficult-to-monitor valves No detectable emissions designation vacuum service In Not in VOC (or VHAP) service Repair Closed-vent systems Control devices incentives to expand scope of VOC source control. Reporting Requirements Table 2-7. District of Columbia, Kentucky, Louisiana, Delaware, New Jersey, New York, North Carolina, Maryland, approval (Illinois, Massachusetts, Michigan, pending Ohio, and Utah) (BNA, 1994; U.S. EPA, Missouri, leak 2.3 State Regulation of VOC Sources 25

38 Major local criteria affecting extent to objectives. such efforts are pursued will be severity of which subject to this regulatory approach. In states sources as California, which regulates air pollution through such regiodal authorities within state, separate of regulatory applications will be even greater. variability current information on controlling-voc Accurate, from equipment leaks is obtained most emissions an NTIS number is cited in a reference, that When is available from: document Port Royal Road 5285 VA Springfield, Bureau of National Affairs, Inc. State VOC BNA. leak regulations: 1990 through equipment search prepared by BNA (Washington, DC) Database Eastern Research Group, Inc., 110 Hartwell for Washington, DC. September. EPA-340/ b. EPA, 1990b. U.S. Environmental Protection U.S. Hazardous waste treatment, storage, and Agency. facilities: Background information for disposal organic emission standards for process promulgated and equipment leaks. EPA-450/ NTIS vents EPA. 1990c. U.S. Environmental Protection U.S. Polymer manufacturing industry-enabling Agency. EPA-450/ NTIS PB document. Triangle Park, NC. December. Research EPA U.S. Environmental Protection Agency. U.S. of state VOC regulations, volume 2. Group Summary regulations. EPA-450/ NTIS PB88- VOC Research Triangle Park, NC. May EPA. 1984a. U.S. Environmental Protection U.S. Control of volatile organic compound leaks Agency. syntic organic chemicals manufacturing from and polymer manufacturing equipment. EPA- industry NTIS PB Research 450/ Park, NC. March. Triangle EPA. 1984b. U.S. Environmental Protection U.S. Fugitive VOC emissions in syntic Agency. OH. December. Available from Office Cincinnati, Research and Development, Center for of Research Information, Cincinnati, OH. Environmental (phone), (fax) EPA. 1983a. U.S. Environmental Protection U.S. Equipment leaks of VOC in natural gas Agency. EPA. 1983b. U.S. Environmental Protection U.S. Control of volatile organic compound Agency. EPA. 1982a. U.S. Environmental Protection Agency. U.S. emission sources of organic compounds: Fugitive in.formation on emissions, emission Additional and costs. EPA-450/ NTIS PB82- reductions, Research Triangle Park, NC. April EPA. 1982b. U.S. Environmental Protection U.S. Background information for Agency. VOC fugitive emissions in promulgated standards. January EPA. 1982d. U.S. Environmental Protection Agency. U.S. fugitive emissions: Background information Benzene proposed standards. EPA-450/ b. NTIS for EPA. 1982e. U.S. Environmental Protection U.S. Vinyl chloride: First review of national Agency. EPA U.S. Environmental Protection Agency. U.S. fugitive emissions in syntic organic VOC manufacturing industry: Background chemicals for proposed standards. EPA-450/3-80- information NTIS PB Research Triangle Park, 033a. November. NC. EPA U.S. Environmental Protection Agency. U.S. of volatile organic compound leaks from Control refinery equipment. EPA-450/ petroleum PB Research Triangle Park, NC. June. NTIS meet VOC control continue to expand as states seek to chemicals manufacturing industry. EPA-625/ organic Research Triangle Park, NC, and (i.e., ozone nonattainment classification) problem types and local distribution of stationary and industry: Background information for production standards. EPA-450/ a. NTIS PB84- proposed through direct contact with appropriate efficiently or local agency. state Research Triangle Park, NC. December. 2.4 References leaks from natural gas/gas processing equipment EPA-450/ NTIS PB plants. Technical Information Service Research Triangle Park, NC. December. National VOC fugitive emissions in syntic Agency. chemicals manufacturing industry: organic Lexington, MA February Avenue, EPA. 1990a. U.S. Environmental Protection Agency. U.S. techniques for ugitive VOC emission Inspection Course module $380, lecturer's manual. sources: EPA-450/ b. NTIS PB Research Park, NC. June. Triangle EPA. 1982c. U.S. Environmental Protection U.S. petroleum refining Background information for proposed industry: Draft. EPA-450/ a. NTIS PB83- standards. PB Research Triangle Park, NC. June. PB Research Triangle Park, NC. June. standards. EPA-450/ NTIS PB84- emission Research Triangle Park, NC. March CTG and greater than 100 tons per year non-ctg III 26

39 leak standards are designed to control Equipment of VOCs and VHAPs from regulated emissions through application of work practices equipment equipment practices. work practice most and applied to control equipment leaks is commonly program, which is discussed in detail in LDAR Subsequent chapters address Section recordkeeping, and reporting requirements monitoring, implementing a LDAR program under NSPS or of standards. In this chapter, regulated equipment NESHAP reviewed to illustrate how monitoring programs are is to specific pieces of equipment. applied practices include use of specific types Equipment components, equipment design standards or of using performance standards that provide a or substantiating effectiveness of such monitoring practices. Equipment practices, briefly control in Section , are addressed in summarized detail in this chapter. greater general set of equipment is covered by all of A leak standards. Some equipment is covered equipment fugitive emission standards cover additional chloride (loading and unloading lines, agitators, slip sources opening of equipment, and in-process gauges, Except for agitators, however, wastewater). from se sources generally are not emissions "equipment leaks." equipment leak considered also identify requirements for closed-vent standards and control devices that may be used to systems Pumps 3.1 are used extensively in SOCMI and Pumps 3 Chapter Equipment Regulated natural gas plants, for moving organic fluids. most processing used pump is centrifugal pump. Or types widely pumps that also may be used are positive- of reciprocating and rotary action, and displacement, transferred by pumps can leak at point of Chemicals between moving shaft and stationary casing. contact isolate pump's interior from atmosphere, all To except seal-less type (canned-motor and pumps, diaphragm), require a housing. most commonly used penetrates in se pumps are packed and mechanical (U.S. seals seals can be used on both reciprocating and Packed action pumps. A packed seal consists of a cavity rotary heat, lubrication is required. A sufficient frictional of liquid (eir liquid being pumped or amount packing and shaft to provide between lubrication. If this packing and/or shaft necessary face degrade after a period of usage, organic seal can leak to atmosphere. compounds Figure 3-1. acking "v canned-motor and diaphragm pumps (U.S. special 1990). EPA, seal at point where shaft EPA, 1980a) Packed Seals and operational standards for certain specifications, of equipment. Equipment practices are evaluated types box") in pump casing filled with special ("stuffing material that is compressed with a packing packing basis for to form a seal around shaft. A simple packed gland is illustrated in Figure 3-1. To prevent buildup of seal anor liquid that is injected) must be allowed to flow by specific standards. For example, product only vessels are covered only by accumulator equipment leak standards for benzene. Also, vinyl st.uffing box '! Pump j j,,nggland comply with regulations. petroleum refinery industries, as well as in Diagram of simple packed seal (U.S. EPA, 1980b). 27

40 seals, limited in application to pumps with Mechanical shafts, can be single or dual. Basic designs of rotating seals vary, but all have a lapped seal face mechanical a stationary element and between rotating seal ring a faces are lapped to a very high degree of element to maintain contact over ir shared surface flatness area (Figure 3-2). faces are held toger by a Glaq g. asket Stationary 1 I=: I)ti==, [" {'element Fluid Figure '( Rotating dng seal of pressure supplied by a spring and combination pressure transmitted through liquid that is pump with anor elastomer or gasket. As with packed box faces must be lubricated; however, because seals, mechanical seal's construction, much less of is needed. Again, if seal becomes lubrication because of wear, organic compounds imperfect pumped can leak between seal faces and being can mechanical seals (Figure 3-3) can be arranged Dual to back, in tandem, or face to face. In back-to- back arrangement, two seals form a closed cavity. A back fluid, such as water or seal oil, is circulated barrier dual seal and lubricates both sets of seal faces, transfer and seal life characteristics of this dual heat are much better than those of single seal. In seal for seal to function, barrier fluid must be at order pressure greater than operating pressure of a box. As a result, some barrier fluid will leak stuffing Possibl sealing into Figure 3-3. arrangements of dual mechanical pump "pical (U.S. EPA, 1984). seals will enter stuffing box and mix with process face Barrier fluid going across outboard face will liquid. to atmosphere. refore, barrier fluid must exit compatible with process liquid and with be (Ramsden, 1978, p. 99). environment a tandem dual mechanical seal arrangement, In face same direction, and secondary seal seals a backup for primary seal. A seal flush is provides in stuffing box to remove heat generated used friction. As with back-to-back seal arrangement, by filled with a fluid. barrier fluid, however, is at barrier pressure a than that in stuffing box. refore, any lower leakage will be from stuffing box into seal cavity Gland late Single Mechanical Seals Seal liquid Seal liquid out (top) in 1978). In a single mechanical seal (Ramsden, rotating-seal ring and stationary application, fluid Fluid end Gland dng Primary Secondary seal seal Back-to-Back Arrangement Seal liquid Out In (top) (bottom) SE S? area p g haft Seal face packing of basic single mechanical seal (U.S. EPA, Diagram 19e0b). pumped. An elastomer seals rotating face to being shaft. stationary face is sealed to stuffing / \/ Primary Secondary seal seal Tandem Arrangement be emitted to atmosphere Dual Mechanical Seals through cavity. Because barrier fluid surrounds cavity between two tandem seals is across seal faces. Liquid leaking across inboard 28

41 barrier fluid. Since this liquid is routed to containing closed reservoir, process liquid that leaks into seal a also will be transferred to reservoir. At cavity process liquid could vaporize and be reservoir, to atmosphere. To ensure that VOCs or emitted do not leak from reservoir, reservoir can VHAPs arrangement of dual seals is face to face. In Anor configuration, two rotating faces are mated with a this stationary barrier. Barrier fluid may be common at higher or lower pressures than in provided box. As in tandem arrangement, if stuffing fluid is at a lower pressure than in stuffing barrier Seal-less Pumps seal-less pump includes canned-motor and pumps. In canned-motor pumps (Figure diaphragm cavity housing, motor rotor, and pump 3-4), suction[ 3.2 Figure 3-4. of seal-less canned-motor pump (US. Diagram 1990, p. 2-11). EPA, run in process liquid and all shaft seals are bearings Because process liquid is bearing eliminated. abrasive solids cannot be tolerated. Canned- lubricant, pumps are used widely for handling organic motor organic heat transfer liquids, light oils, and solvents, toxic or hazardous liquids. Canned-motor pumps many are used when leakage is an economic problem also and Chilton, 1978, p. 6-8). (Perry pumps (Figure 3-5) perform similarly to Diaphragm and plunger pumps. driving member, piston 3-5. Diagram of diaphragm pump (U.S. EPA, 1990, Figure 2-13). p. or plastic. primary advantage of this rubber, is that no packing and shaft seals are arrangement to process liquid, which is an important exposed when handling hazardous or toxic liquids: asset Compressors industries affected by se standards, In reciprocating, and rotary compressors are centrifugal, centrifugal compressor uses a rotating used. volume of cavity. Reciprocating decreasing usually use a piston and cylinder compressors with pumps, seals are required to prevent leakage As compressors. Rotary shaft seals for compressors from be labyrinth, restrictive carbon rings, mechanical may or liquid film. Figure 3-6 is an illustration of contact, are leak restriction devices, but none of m seals eliminates leakage. To respond to leakage, completely many compressors are equipped with ports in be vented to a control device. Diaphragm barrier, fluid reservoir may require venting to a box, device. control Piston are interconnected. As a result, motor casing Discharge I. lating tube or series of elements containing curved blades element Bearings to increase pressure of a gas by centrifugal force. Impeller and rotary compressors increase pressure Reciprocating confining gas in a cavity and progressively by while rotary compressors use rotating arrangement, such as lobed impellers or sliding vanes. elements typical designs of se four types of seals. All of se seal area that evacuate collected gases. however, is a flexible diaphragm fabricated of metal, 29

42 may be added Port scavenging or for Internal pressure gas Labyrinth Seal Contaminated out oil Single Mechanical Seal J Pressure.Rotating seat may be Port for added Internal gas Figure 3-6. Typical designs of mechanical compressor seals (Ramsden, 1978, p. 99). gas Contaminated Oil out pressure Liquid Film Seal Scavenging may be port for added vacuum application inert-gas sealing sealing Atmosphere pressure Atmosphere Restrictive Ring Seal Clean oil in / breakedown bushing Outer I lnner [/ Shaft sleeve,, Atmosphere out oil 30

43 Labyrinth labyrinth seal is composed of a series of close interlocking "teeth" that restrict flow of tolerance, along shaft. Many variations in "tooth" design gas materials of construction are available. Although and seals as a group have largest leak labyrinth of different types, properly applied potential in tooth configuration and shape can reduce variations Carbon Rings ring seals consist of multiple Restrictive'carbon carbon rings with close shaft clearances. stationary seals may be operated dry with se sealing fluid or a a buffer gas. Restrictive ring seals with achieve can leak rates than can labyrinth type. lower contact seals are a common type of seal for Mechanical compressor shafts and are similar to rotary seals described for pumps. In this type of mechanical clearance between rotating and stationary seal, is reduced to zero, and oil or anor suitable elements is supplied to seal faces. Mechanical seals lubricant achieve lowest leak rates of types can here, but y are not suitable for all discussed seals are used for reciprocating compressor Packed As with pumps, packing in stuffing box is shafts. with a gland to form a seal. Packing used compressed reciprocating compressor shafts is often of on or netted V type. To ensure operating safety, "chevron" area between compressor seals and motor (distance piece) normally is compressor and vented outside of compressor enclosed Reciprocating compressors can use a and nonmetallic partially compressible material plate Graffoil, Teflon) or oil wiper rings to seal shaft (i.e., to distance piece. Neverless, leakage some into distance piece may occur. leakage addition to having seal types like those used for In centrifugal compressors can be equipped pumps, a liquid-film seal. seal is a film oil that with between rotating shaft and stationary flows oil that leaves compressor from gland. system side is under system internal pressurized contaminated oil is returned to open oil this process gas and entrained VOCs and VHAPs reservoir, pressure may exceed maximum allowable process pressure of vessel. pressure relief working is most common type of pressure-relieving valve used. Typically, relief valves are spring-loaded device Figure 3-7) and designed to open when (see pressure exceeds a set pressure, allowing system of vapors or liquids until system pressure is release to its normal operating level. When normal reduced Figure 3-7. Possible area leak is re-attained, valve reseats, and a seal is pressure formed. seal is a disc on a seat, and again leak a this seal is a potential source of VOC and through fugitive emissions. potential causes of VHAP from relief valves are "simmering or popping" leakage condition that occurs when system pressure (a close to set pressure of valve); improper comes of valve after a relieving operation; and reseating or degradation of valve seat (U.S. EPA, corrosion p. 3-3). 1980a, contaminated with gas. When gas pressure and is can be released to atmosphere. 3.3 Pressu'e Relief Devices codes require tle use of pressure- Engineering devices or systems in applications where relieving by up to 40 percent over leakage straight-pass-type a (Nelson, 1977). labyrinth Mechanical processing Packed If hydrogen sulfide is present in gas, n building. vented vapors are flared normally. Pi'ocess side metallic packing of a spring-loaded relief valve (U.S. EPA, Diagram p. 2-16). 1990, Liquid Film Seals 31

44 Rupture discs also may be used to units (see Figure 3-8). se discs are made process a material that ruptures when of set pressure is a thus allowing system to depressurize. exceeded, advantage of a rupture disc is that disc seals and does not allow any VOC tightly VHAP to escape or system during normal operations. When from ruptures, however, system will depressurize disc atmospheric conditions are obtained, unless until disc is used with a pressure relief valve. To atmospheric Seat relief Pressure valve disc Rupture Figure 3-8. Rupture disc for Connection gauge pressure design of a pressure relief valve mounted Typical a rupture disc device (Ramsden, 1978, p. 99). on samples for se analyses, sampling representative first must be purged. If flushing liquid is not lines it could be drained onto ground controlled, into a or drain where it would evaporate and release process or VHAPs to atmosphere. Closed-loop VOCs systems control purged process fluid by sampling it directly to process line, collecting and returning fluid, or transporting fluid to recycling control a se sampling system controls typically allow device. VOC or VHAP emissions to atmosphere. zero closed-loop sampling systems are illustrated in Two Figure 3-9. Figure 3-9. valves are installed in a system Some that y so with downstream line open to function drain, and sampling lines. Some open-ended purge, are needed to preserve product purity. Normally, lines are installed between multi-use product lines to se products from collecting in cross-tie lines prevent valve seat leakage. A faulty valve seat during or closed valve would result in leakage incompletely requirements specify that open-ended Operational or lines be equipped with a cap, blind flange, valves or second valve. purpose of cap, blind plug, plug, or second valve is to seal open end at flange, times, except during operations requiring process all flow through open-ended valve or line. fluid a second valve is used, open-ended line or valve If to be operated so that valve on process fluid is is closed before second valve is closed. If a end block-and-bleed system is being used, double all or times, open end of bleed valve At line or be sealed (again, except during operations must of most common pieces of equipment affected One se standards is process valve. Commonly by types are control, globe, gate, plug, ball, relief, used check valves (see Figures3-10 and 3-11). All and relief valve (see Section 3.3) and check except are activated through a valve stem, which may valve relieve pressure in Process line container Tension-adiustment Sample of two closed-loop sampling systems Diagram 1978, p. 99). (Ramsden, 3.5 Open-ended Lines or Open Valves Open-ended lines, which atmosphere. used mainly are intermittent service for sampling and venting, include in Disc vent Blind flange valve, releasing fugitive VOC or VHAP through to atmosphere. emissions device and bleed valve From system may.remain open during operations Sampling Connections 3.4 unit operations are checked periodically by Process bleed valve or line that require venting line between block valves. feedstocks and products. To obtain routine analysis of process fluid flow through open-ended requiring or valve). line 3.6 Process Valves 32

45 3-10. Diagram of a globe valve with a packed seal (U.S. Figure 1980b). EPA, Potential areas /leak Figure Diagram of a ball valve (U.S. EPA, 1990, p. 2-21). have eir a rotational or linear motion, depending on design. valve stem requires a seal to isolate fluid inside valve from atmosphere. process of a leak through this seal makes it a possibility source of fugitive emissions. Since a check potential has no stem or subsequent packing gland, it is valve considered a potential source of fugitive emissions. not stem can be sealed to prevent leakage by using a gland or O-ring seals. Valves that require packing and out with or without rotation must use packing gland. Conventional packing glands are suited a a wide variety of packing material. most common for various types of braided asbestos that contain are Or packing materials include graphite, lubricants. packing glands can be used over a but at high pressures, se glands must temperatures, quite tight to obtain a good seal (Templeton, 1971 ). be O-rings also are used for sealing process Elastomeric se O-rings provide good sealing, but are not valves. if sliding motion occurs through packing suitable se seals are used rarely in high pressure gland. and operating temperatures are limited by service, material. seal seals are more effective for preventing process Bellows leaks than is conventional packing gland or fluid or gland-seal arrangement. This type of seal any a formed metal bellows that makes a incorporates between disc and body bonnet joint (see barrier 3-12). bellows is weak point of this type Figure system, and service life can be quite variable. of this type of seal normally is backed up Consequently, a conventional packing gland and often is fitted with a leak detector in case of failure. with valve and environment from process of Illustrated in Figures 3-13 and 3-14 are two types liquid. diaphragm seals. diaphragm also may be used of control flow of process fluid. In this design, a to component pushes diaphragm toward compressor valve bottom, throttling flow. diaphragm and are connected in a manner so that compressor m is impossible under normal working separating When diaphragm reaches valve conditions. it seats firmly against bottom, forming a bottom, leak-proof seal. This configuration is containing solid particles and for medium- fluids service. Depending on diaphragm pressure this type of valve can be used at temperatures material, to 205 C and in severe acid solutions. If seal up fails, however, a valve using a diaphragm seal can,,,,handwheel stem to move in fibers, and tetrafluorethylene graphite-impregnated packing material used depends on polymer. valve application and configuration. se conventional range of operating Seat Body Disc A diaphragm may be used to isolate working parts 0 recommended for 33

46 3-12. Diagram of a sealed bellows valve (U.S. EPA, 1990, Figure 2-23). p Diagram of a weir diaphragm seal (U.S. EPA, 1990, Figure 2-24). p. Figure a source of fugitive emissions (Pikulik, 1978, become 3-23 and 3-24). pp. are bolted, gasket-sealed junctions used Flanges pipes or or equipment such as vessels, wherever valves, and heat exchangers may require pumps, or removal. Connectors are all or isolation fittings that serve a similar purpose to nonwelded which also allow bends in pipes (elbows), flanges, two pipes (couplings), or joining three or four joining (tees or crosses). Connectors typically are pipes may become fugitive emissions sources when Flanges occurs because of improperly chosen gaskets leakage poorly assembled flanges. primary cause of or leakage is rmal stress,., which causes flange of seal between flange faces. deformation connectors may leak if threads become Threaded or corroded or if tightened without sufficient damaged or torque. LDAR programs are principal lubrication background information document for benzene standards (U.S. EPA, 1980b) states proposed product accumulator vessels include overhead and that receiver vessels used with fractionation bottoms Diaphragm Bellows of a bonnet diaphragm seal (U.S. EPA, Diagram p. 2-24). 1990, 3.7 Flanges and Or Connectors threaded. Weir //# Diaphragm control technique for flanges and or connectors. 3.8 Product Accumulator Vessels and product separator vessels used in series columns

47 reactor vessels to separate reaction products. with vessels can be vented directly to Accumulator or indirectly through a blowdown drum or atmosphere system. When an accumulator vessel contains vacuum and vents to atmosphere, benzene benzene can occur. This equipment is covered only by emissions benzene standards require each product vessel to be equipped with a closed-vent accumulator devices include vapor recovery systems, control combustion devices, or flares. se control- enclosed systems are described in Section Agitators 3.9 are used to stir or blend chemicals. Like Agitators Consequently, seals are required to minimize casing. emissions. Four seal arrangements commonly fugitive used with agitators: compression packing (packed are mechanical seals, hydraulic seals, and lip seals. seal), seals for agitators are very similar in design Packed application to packed seals for pumps (Ramsey and Zoller, 1976). and mechanical seals are more costly than Although three types of seals, y offer a greatly reduced or rate to offset ir higher cost. Furrmore, leakage maintenance frequency of mechanical seals is one- to one-fourth that of packed seals, At pressures half than 1,140 kpa (150 psig), leakage rate and greater frequency are so superior that use of maintenance packed seals on agitators is shaft seal, has an annular cup attached to agitator vessel that contains a liquid that is in contact process an inverted cup attached to rotating agitator with primary advantage of this seal is that it is a shaft. temperatures and pressures, and very small low fluctuations. In addition, organic chemicals pressure contaminate seal liquid and n be released may atmosphere as fugitive emissions. into seal can be used on a top-entering agitator as a or vapor seal. sealing element is a spring- dust elastomer. Lip seals are relatively inexpensive loaded easy to install. Once seal has been installed, and agitator shaft rotates in continuous contact with temperatures are limited by characteristics of Fugitive emissions can be released through elastomer. seal when seal wears excessively or this Closed-Vent Systems and Control 3.10 Devices closed-vent system can be used to collect and A of gaseous VOC emissions, from seal oil dispose of over-pressure operation. A closed-vent because consists of piping connectors, flame arrestors, system if necessary, flow-inducing devices. Closed-vent and, are designed and operated so that all VOC systems are transported to a control device without emissions to atmosphere. leakage types of control devices can be used to dispose Several VOC and VHAP emissions captured in closed- of system. Incineration, carbon adsorption, and vent are three control methods that typically condensation dependent on specific operating characteristics and are types of emissions being generated. Typically, combustion devices (boilers, process heaters, enclosed rmal and catalytic incinerators) can achieve and than 95 percent destruction efficiencies. key better affecting destruction efficiency are residence parameters design and operation, while condensation proper can achieve capture efficiencies of 90 percent systems commonly found at plants subject to se Flares include steam-assisted, air-assisted, non- standards ground, and dual-flare systems. Certain flares assisted, demonstrated destruction efficiencies equal to have of enclosed combustion devices provided certain those specifications (heat content and exit velocity) design an NTIS number is cited in a reference, that When is available from: document Technical Information Service National Port Royal Road 5285 VA Springfield, W.E Compressor seal fundamentals. Nelson, Processing 56(12): December. Hydrocarbon R.H. and C.H. Chilton Chemical Perry, Handbook, 5th Edition. McGraw-Hill Book Engineer's Company, New York, NY. pp pressure surpasses pressure limits of operating seal. benzene equipment leak standards. capable of capturing and transporting any system from vessel to a control device. Acceptable leakage vents, pump and compressor seal leakage, degassing valve leakage, and relief valve discharges relief pumps and compressors, agitators may leak organic chemicals at point where shaft penetrates three methods are applied. Control efficiencies of and temperature. Carbon adsorption systems can time 95 to 99 percent control efficiency through achieve or more. rare. As with packed seals, mechanical seals for agitators are similar in design application to mechanical seals for pumps. and hydraulic seal, which is simplest and least used are met (U.S. EPA, 1985). noncontact seal. Use of this seal, however, is limited to 3.11 References A lip seal. Pressure limits of seal are 2 to 3 psig lip it operates without lubrication, and operating because 35

48 A Manually operated valves. Chemical Pikulik, 85(7):121. April 3. pp. 3-23, Engineering J.H How to choose and install Ramsden, seals. Chemical Engineering 85(22):97- mechanical W.D. and G.C. Zoller How design of Ramsey, seals and impellers affects agitator shafts, EPA U.S. Environmental Protection Agency. U.S. techniques for fugitive VOC emission Inspection Course module $380. Student's manual. sources: Washington, DC. September. EPA-340/ a. EPA U.S. Environmental Protection Agency. U.S. manufacturing industry: Background Polymer for proposed standards. EPA-450/3-83- information NTIS PB Research Triangle Park, 019a. EPA U.S. Environmental Protection Agency. U.S. VOC emissions in syntic organic Fugitive manufacturing industry. EPA-625/ chemicals Research Triangle Park, NC, and Cincinnati, 004. EPA. 1980a. U.S. Environmental Protection U.S. VOC fugitive emissions in syntic organic Agency. manufacturing industry: Background chemicals for proposed standards. EPA-450/3-80- information NTIS PB Research Triangle Park, 033a. November. NC. EPA. 1980b. U.S. Environmental Protection U.S. Benzene fugitive emissions: Background Agency. for proposed standards. EPA-450/3-80- information NTIS PB Research Triangle Park, 032a. OH. December October 9. Chemical Engineering 83(18): performance. 30. August H.C Valve installation, operation and Templeton, Chemical Engineering 78(23):141- maintenance October 11. NC. November. NC. September. 36

49 comply with equipment leak standards, a monitoring To screening program to identify leaking components or be implemented. Screening equipment for potential must is fundamental to LDAR programs, and information leaks screening equipment components with a portable for an.lyzer. To give perspective of a unit-wide organic plan, overall survey procedure is screening first. n, selecting an appropriate portable presented subject to LDAR programs. chapter components with a brief discussion on data handling and concludes calibration procedures for quality assurance. screening survey first must define precisely unit boundaries. This definition is usually process but sometimes multiple units share straightforward, A process unit is smallest set of process facilities. that can operate independently and includes equipment operations necessary to achieve its process objective. all survey should document exact basis for definition, and a plot plan of unit should be unit with appropriate boundaries. To screen marked in.a unit, all equipment to be included in equipment needs to be identified. A list of equipment types that unit subject to LDAR programs is provided in Table 4-1 are EPA, 1988).Not all facilities will contain each of (U.S. equipment components. Also identified in Table se next step is to obtain a simplified process flow and note process streams. screening diagram data collection can be done most systematically by and each stream. For instance, a logical starting following 4 Chapter Requirements Monitoring seals Pump seals Compressor Valves relief devices Pressure connections Sampling screwed connections, etc. Flanges, lines Open-ended vents, doors Drains, Agitator seals Gas/vapor liquid Light source that has been screened should be clearly Each for example, with wearproof,, corrosion- marked, and readily visible identification. Alternatively, resistant, process unit is appropriately identified if unit has a a of markings, with an associated diagram, that system easy location of marked sources. allows screened, unit should be divided into a grid to been for fittings missed on initial survey. unit search is complete when all sources in unit have survey eir screened or identified as nonhydrocarbon been Leakless equipment and equipment not in components. (or VHAP) service should not be included in VOC Equipment documented as inaccessible, survey. should be included in survey; under however, leak standards, such equipment must be equipment annually. screened with equipment leak standards for hazardous Consistent pollutants, unsafe-to-monitor components do not air Table 4--1, Fugitive Emission Sources (U.S. EPA, 1988) Equipment Types by screening programs also supports generated and reporting programs (described in recordkeeping 5) that are necessary for demonstrating Chapter with regulations. compliance Presented in this chapter are protocols and methodologies Service instrument is discussed, and screening monitoring are given for different equipment protocols Heavy liquid 4.1 Overall Survey Procedure screening all sources, until its termination at flanges of a reactor or separation step. Once all of equipment along major streams has are types of sources in which se equipment 4-1 might be found. components need to be included in survey. Documentation must is where feed line enters process point screening team follows that. line, boundary. 37

50 provided, however, to substantiate unsafe nature be such equipment. of equipment leak standards only address specific Although of equipment to be monitored, additional factors pieces be important to monitoring program organization. might factors to consider include Some to identify measures not accessible to routine monitoring; steps to sources missing pieces of equipment that should be avoid and consideration of additional applications monitored; data generated, such as developing emission of portable VOC detection analyzers Many measure can from equipment components. se devices leaks on a variety of principles, but three most operate are ionization, infrared absorption, and common combustion. Any analyzer can be used provided it specifications and performance criteria in EPA Method 21 (see Appendix C). All analytical Reference are permitted provided y instruments shown to are organic compounds of interest and measure are related to EPA's data base, which results was using a flame ionization detector (FID), generated to methane (U.S. EPA, 1981a,b; 1980). calibrated factors (RFs) must be developed for Response analytical instruments referenced to compounds or methane (see Section 4.2,2.1) to relate screening than to actual monitored chemical concentrations. values alternative allows use of many instruments that This be calibrated with methane. cannot Operating Principles and Limitations of VOC Detection Devices Portable detectors operate by ionizing sample and Ionization measuring charge (number of ions) produced n EPA, 1986, 1988, pp. 3-4 and 3-5). Flame ionization (U.S. photoionization are two methods of ionization and mixtures. An FID also may be used as a nonspecific for gas detector for a organic components. Carbon monoxide (CO) individual carbon dioxide (CO2) do not produce interferences, and compounds containing nitrogen (N), oxygen organic or halogen atoms give a reduced response when (O), with an FID, and some organics might not give sampled response at all. For this reason, RFs must be any for each compound that is to be measured. developed Section for a discussion of RFs. See detectors (PIDs) use ultraviolet light Photoionization of a flame) to ionize organic vapors. As with (instead detect leaks in process units used in SOCMI, to for compounds such as formaldehyde that especially not give a response on an FID do combustible or detector. infrared (NDIR) instruments Nondispersive measure absorption characteristics of gases. NDIR light usually are subject to interference from instruments gases such as water vapor and CO2 that may or light at same wavelength as a compound of absorb se detectors generally interest. used only for are detection and measurement of single components. detect and measure single components, To at which a certain compound absorbs wavelength radiation is predetermined, and device is infrared for that specific wavelength using optical filters. preset example, if set to a wavelength of 3.4 micrometers, For devices can detect and measure petroleum infrared including gasoline and naphtha. fractions, analyzers are designed to measure eir Combustion rmal conductivity of a gas or heat produced heat of combustion--se devices are referred to hot,wire detectors or catalytic oxidizers. Combustion as like most or detectors, are nonspecific for analyzers, mixtures. In addition, combustion analyzers exhibit gas response (or, in some cases, no response) to reduced that are not combusted readily, such as gases formaldehyde and carbon tetrachloride. Performance Criteria and Evaluation Portable VOC Detectors for as. a screening device provided it meets used criteria specified in Reference Method 21 performance applied to Although portable detectors can be universally. Facilities may need to develop applied an method for testing some organic alternative A discussion of performance criteria compounds. portablevoc detectors is presented in following for and summarized in Table 4-2 (40 CFR Part 60). section addition to performance criteria, Reference In 21 requires that analyzer meet se Method specifications: VOC detector shall respond to those organic being processed (determined by RF). compounds FIDs, detector response varies with functional group in organic compounds. PIDs have been used estimates (see Chapter 7). 4.2 Monitoring Instruments meets combusting gas. most common method by in portable combustion analyzers is measuring used As stated earlier, any portable VOC detector may be used. A standard FID usually measures currently carbon content of organic vapor sampled, total (see Appendix C). many organic, compounds, y cannot be which means that an FID reading is gas chromatograph (GC) to measure concentrations of FID analyzers do react--at a low sensitivity-- although water vapor. Furrmore, if water condenses in to sample tube, erratic readings can result. A filter is used to remove particulate matter from sample. Certain analyzer shall be capable of measuring leak specified in regulation (i.e., 10,000 definition ppmv or "no detectable limit"). 38

51 Must be less than One time, before detector Instrument factor 10 unless correction is put in service. response be less than or Must to 30 seconds equal time, before detector One put in service. If is to sample modification or flow pumping ismade, a contiguration test is required. new Must be less than or Before detector is put in Calibration equal to 10% of service and at 3-month precision 40 CFR Part 60, Appendix A. Reference Method 21, From of Volatile Organic Compound Leaks." =Determination scale of analyzer shall be readable to +5 of specified leak definition concentration. pement analyzer shall be equipped with a pump so that continuous sample is provided at a nominal flow a analyzer shall be intrinsically safe for operation explosive atmospheres. in for calibration gases to be used also are Criteria Two or more gases are required for analyzer specified. gases), which use reference compounds in reference mixtures. concentration of reference gas air represent range of responses measured. To should unit-specific emission estimates, a reference develop an analyzer is calibrated with a reference gas, an When response will not be obtained for or equivalent because analyzer responds differently to gases compounds. An RF is required to provide an different relationship between a calibrated analyzer accurate anor compound. If an FID is calibrated for and for example, a direct reading from methane, assumes equivalent responses for methane instrument any or compound. RF helps to quantify and analyzer responds differently toward each how Response Factor RF of 1.0 means that instrument readout is An to actual concentration of chemical in identical gas sample. A higher RF results in an instrument that is propqrtionally lower than actual readout A high RF means that a given instrument concentration. not detect a compound very well. following does illustrate this definition (U.S. EPA, 1990). examples 1: Example of an instrument with an RF of 10 for specific use would allow an actual concentration of chemical(s) ppmv. Conversely, use of an instrument 100,000 an RF of 0.1 would indicate that regulatory limit with is only 1,000 ppmv. Typical RFs range concentration 0.1 to 40. lower RF, more sensitive a from accordance with Reference Method 21, only In with RFs of less than 10 for monitored instruments compounds may be used for leak detection. organic RF must be determined eir by consulting tabular data provided by instrument published or EPA, or, alternatively, by laboratory manufacturers specific instrument being used with testing of interest. Although, latter approach is chemicals many compounds. Manufacturers of RFs or multipliers used to correct instrument about information from manuals, measurement. is basic background ory and is not explicit however, EPA, 1992a). (U.S. RF may be used as a guide in selecting an monitoring device. For example (see appropriate D, Table D-l), when screening equipment in a Appendix unit containing cumene, an FID can be used process Performance Criteria for Portable VOC Detectors* Table 4-2. Criteria Requirement Time Interval curve is used Instrument response time Actual concentration ppmv 10,000 gauge reading 5,000 ppmv Instrument or next use, intervals is later. whichever factor 2 Response 2: Example calibration gas value Actual concentration ppmv 1,000 gauge reading 3,000 ppmv Instrument factor 0.33 Response 3: Example Actual concentration ppmv 100,000 gauge reading 10,000 ppmv Instrument rate of between 0.5 and 3.0 liters per minute. factor 10 Response regulatory limit is 10,000 ppmv (observed), If evaluation: a zero gas, which is air with performance than 10 ppmv VOCs; and calibration gases (or less of 10,000 ppmv had been exceeded when actual instrument is for a specific type of organic given compound. gas for appropriate range should be selected Response Factors more accurate, it is very expensive for instruments that are used for portable analyzers include information in ir manuals (U.S. EPA, 1992a). RF is defined by compound equation: following Actual concentration of compound Observed concentration from detector 39

52 1.87); while oxidation detector cannot be used (RF has no catalytic Similarly, from same data (Appendix D, value). detecting leaks from a source containing carbon of if RF adjustments were not used (U.S. tetrachloride 1981a). EPA, RFs have been published for compounds of If results may be referenced. Results of several existing developing RFs of portable analyzers are studies Inc., no date). se RFs can be used Development, determining if a screening concentration is above when below 10,000 ppmv. ( values are for pure organic or only.) Presented in Table D-2 of Appendix D chemicals instrument response of 10,000 ppmv at any feasible an unless RFs are used (U.S. EPA, 1981a). concentration single RFs are adequate for RF adjustments se using a portable VOC detector as a screening when response time of an analyzer refers to ability of instrument to respond to presence of a VOC Response time is defined as time concentration. from a step change in VOC concentration at interval of a sampling system to time at which 90 input of corresponding final value is reached as percent be determined for analyzer configuration that must be used during testing. response time must be will before placing an analyzer in service. If a tested to sample pumping system or flow modification configuration is made that would change response a new response time test is required before time, screening program. continuing precision is degree of agreement Calibration measurements of same known value. To between that readings obtained are repeatable, a ensure precision test must be completed before calibration next use, whichever is later. calibration or must be less than or equal to 10 percent of precision test calibration precision, a total of three measure- To are required for each nonzero concentration. ments introducing zero gas adjusting analyzer to zero. n, specific and (reference) gas is introduced and meter calibration computed. This average is divided by known calibration value and difference by 100 to express resulting calibration multiplied Safety hazardous locations, such as petroleum refineries In bulk gasoline terminals, portable instruments are and to detect VOC emissions from equipment leak required National Electrical Code requires that sources. used in hazardous locations are certified to instruments operate in locations are divided into three classes: Hazardous I, Class II, and Class II1o Each class is divided into Class divisions (Division or 2) according to two that a hazardous atmosphere will be probability and divisions are separated into seven groups present, on type of hazardous material exposure. depending A through D are flammable gases or vapors, Groups Groups E, F, and G apply to combustible or and gases. Class I, Division 1, Groups A, B, C, conductive D locations are those in which hazardous and of flammable gases or vapors might concentrations under normal operating conditions. Class I, exist Groups A, B, C, and D locations are those in hazardous concentrations of flammable gases or which might exist only under unlikely conditions of vapors operation. of 1992, over a dozen manufacturers produced As VOC detection instruments that are certified as portable safe (Analytical Instrument Development, intrinsically no date). Listed in Table 4-3 are manufacturers, Inc., model numbers, instrument certification instrument and performance specifications for se categories, Newer instruments also might be available instruments. meet performance requirements for generating that estimates. emission Monitoring Devices for Difficult Situations some cases, a monitoring device might not be In that meets all of performance specifications available Reference Method 21. For example, in case of of RF at 10,000 ppmvis greater than 10. phosgene, as a Method 21 instrument because it cannot meet fails RF requirement. instrument still can be used to for equipment leaks, however, provided screen is shown to be sufficiently reliable in instrument directly, with no correction for RF (RF is recorded. Next, average algebraic reading between meter readings and known difference Table D-2), neir of se devices would be capable value of calibration gas is precision as percent. detector and calibration interest for combination of gas desired, RF determination is not required, and in Tables D-1 and D-3 through D-5, Appendix presented (U.S. EPA, 1981a, 1982; Analytical Instrument D be explosion-proof and intrinsically safe to defined hazardous locations. are tested compounds that appear unable to achieve device Response Time Division 2, on analyzer readout meter. response displayed must be equal to or less than 30 seconds, and it time 4.2.2,3 Calibration Precision placing analyzer in service and at 3-month intervals calibration gas value. instrument might meet all or requirements, but Measurements are made by first 40

53 Table 4-3. Portable VOC Detection Instrument Performance Specifications (U.S. EPA, 1992b) Leak Deflnifion 5% Meets Definition 10,000 at.instrinslcally 500 Model ppmv ppmv Leak Level Safe Manufacturer n. Sample Flow Response (sec) o.d. Probe (L/rain) Comments Time Foxboro OVA 88 no yes yes no Company yes 108 no yes yes yes 2 yes 2.0 OVA OVA 128 yes no yes* yes 2 yes 2.0 DP-III yes yes yes no* 3 Heath 2.0 Consultants, yes DP-II Inc. no no no* 3 yes 2.5 yes PF-li yes no yes* no* 2 yes 0.7 GasCorder no no* no* no* 3 MSNBaseline 0.5 Industries, yes FID Inc. Sensidyne, Inc. Portable FID yes yes yes no* 3 yes yes no no no 5 rmo 1.5 Environmental yes yes yes yes no 5 yes Instruments, Inc. Comments: Working on making intrinsically safe instrument. 1. Plans are under way to make DP III intrinsically safe. 2. Plans are under way to make DP II intrinsically safe. 3. Foxboro OVA 88 Methane 0-100,000 OVA 108 Methane 0-10,000 Company DP-III Methane 0-10,000 Heath DP-II Methane 0-1,000 Consultants, GasCorder Methae 0-10,000"* MSA/Baseline Inc. FID Industries, 710 Methane 0-2,000 rmo 712 Methane 0-20,000 Environmental Comments: OVA 88 is primarily for natural gas leak detection. 1. analog scale. Logarithmic Generally accepted as industry standard. Logarithmic 2. scale. analog GC option ($1,200) for qualitative analysis. Three scales 3. Currently being modified to be intrinsically safe. 4. Will reach market 9/91 and will be redesigned to meet Class I, 5. and 2 standards by approximately 12/92. Division Five percent definition at 500 ppmv leak level. 6. Dimensions (in.) and Temperature Price* Battery/Fuel 9x12x4,11 8 9x12x4, x7x 10, x7x9, x 4 x 8.5 (Case) x 6.1 x 4 (Gun) 8 to 40 4, to 40 6, to 48 3, to 48 4, to 40 5, to 40 5, Three scales 0-200, -2,000, -20,000. Digital readout. 4. Three scales 0-2,000, -20,000, -200,000. Digital readout. 5. Two scales 0-1,000, 0-10,000. Analog scale. 6. Five scales maxima of 10, 50, 100, 1,000, and 10, Five scales maxima of 10, 50, 100, 500, and 1, Three scales 0-50, 0-500, 0-5,000. Analog scale Flame Ionization Analyzers. Method 21 Criteria 4,6 See Comments. Flame Ionization Analyzers Maximum Range Calibration Manufacturer Model Gas (ppmv) Life (hr) Weight (Ib) (Celsius) ($) Comments 8 9x12x4,12 OVA 128 Methane 0-1, to 40 6,600 3 Inc. -20 to 48 2, x10x9,6.3 PF-II Methane 0-5, x 11.2 x8, to 35 6, Sensidyne, Inc. Portable FID Methane 0-10, x 4.6 x 9.3, to 40 4,800 6 Instruments, Inc. 14 total base unit pdce 8/91. Approximate Comments. See 0-10,-100,-1,000. Linear analog scale. 10. Dedicated air and hydrogen cylinders. Data logging capabilities. 41

54 Leak Deflnltlon 5% Meets Deflnltlon 10,000 at Instrlnslcally Response 0.25-In. Sample Flow 500 Model ppmv ppmv Leak Level Safe Time (sac) o.d. Probe. (L/rain) Comments Manufacturer DL DL GasCorder PID no no yes 3 yes 0.17 yes no no no* 3 yes 0.25 yes no* yes* no* 3 yes 0.5 yes yes Photon yes no yes* no* 3 yes 0.5 MSA International Sensing Scentogun yes no yes* no 2 yes* 0.1 Sentex Inc. Technology, 580-S yes no yes* yes 2 yes 0.4 rmo 580-B Environmental no no no 2 yes 0.4 no Instruments, Inc. Comments: Class I, Division 2 certified. 1. Meets Method 21 probe size criteria only when used with optional extension. 2. Will be redesigned approximately months after it reaches market (9/91) to meet Class I, Division and 2 requirements. 3. Range Battery/Fuel (in.) and Temperature Price* Calibration Model Gas (ppmv) Life (hr) Weight (Ib) (Celsius) ($) Comments Manufacturer Systems, IS-101 Benzene, 0-2, x 5 x 9, to 40 5,000 HNu Isobutylene Inc. MSA International Sensing Sentex Inc. Technology, Benzene 0-2, x 3 x 6, readout 4 40 max 4,900 2 DL Benzene 0-2, x 3, probe 3 40 max 5,500 3 DL Scentogun Benzene 0-2, x 6 x 4, 4 None supplied 3, S Benzene 0-2, x 5.75 x 10, to 40 5,300 4 rmo 580-B Benzene 0-2,000 8 Environmental x 5.8 x 10, 6 5 to 40 4, Instruments, Inc. base unit price 8/9i. Approximate Comments. See Comments: Basic instrument is P HW-101 (Hazardous Waste) is Class I, 1. 2 certified. Analog readout, three scales.9.5, 10.2, 11.7 ev lamps. Division DL has two modes of operation, data logging capabilities, digital , 10.2, 11.7 ev lamps. readout, DL has four modes of opera,on, data logging capabilities, digital 3. Digital display, data logging capabilities, optional bar code 4. interface. reader Digital display, data logging capabililies, 10.6 ev lamp. 5. Digital display, 10.6, 11.5 ev lamps. 6. Dilution system available. 8.4, 9.6, 10.2, 10.6, 11.8 ev lamps. 7. logging capabilities. Data (continued) Table 4-3 Photolonlzatlon Analyzers Method 21 Criteria HNu Systems IS-101 Inc. yes no yes* no* 3 yes 025 1,4 3,4 MSNBaseline 1,4 2,4 4 See Comments. 4. Five percent definition at 500 ppmv leak level. Photoionization Analyzers Maximum Dimensions 8 x 3 x 6, readout 4 GasCorder PID Benzene 0-2,000"* 8 17 x 8 x 8, 10 5 to 35 5,000 7 MS/VBaseline Photon Isobulene 0-2, x 3.8 x 5.8, 7 0 to 40 5,000 5 readout, 9.5, 10.2, 11.7 ev lamps. 42

55 Leak Definition 5% Meets Definition 10,000 at Instrlnslcaliy Response n. Sample Flow 500 Model ppmv ppmv Leak Level Safe Time (sec) o.d. Probe (L/min) Manufacturer Comments Jerome 431X no no no Arizona 13 yes Instrument no 631X no no no no 6 Jerome yes Inc. TLV sniffer yes yes yes yes <30 Bacharach, 1.75 yes no no no no 5 MV-2 N/A 2 yes Gaseeker yes yes CEA yes* <10 yes instruments, no GS4 Inc. Foxboro M IRAN 1Bx yes no yes* Compound no 30 Company yes dependent Gas Tech, Inc yes no yes* yes* <10 yes yes no yes* yes* < yes no yes yes no* 5 GP yes Gasurveyor 4 yes no yes* McNeil 5 yes 0.5 International yes Comments: Internal library of approximately i5 compounds. 1. No sample flow given. 2. Scale reads in milligrams per cubic meter. 3. Four scales ppbv, ppmv, 1-10 ppmv, and Response time varies by scale and mode setting (survey mode times given). ppmv. Meets Method 21 criteri only when used with optional sample 5. attachment. pump BASEEFA certification is pending. 6. Intrinsically safe Class I, Division 1, Groups C and D. 7 Submitted for UL safety approval Leak definition at 500 ppmv. Range Battery/Fuel (in.) and Temperature Price* Calibration Model Gas (ppmv) Life (hr) Weight (Ib) (Celsius) ($) Manufacturer Comments Jerome 431X N/A Arizona 13 x 4, 7 0 to 40 5,900 4 x (mg/m3) Instrument Jerome 631X N/A x 13 x 4, 7 0 to 40 9,900 4 Inc. TLV sniffer Hexane 0-10,000"* 8 9 Bacharach, 3.75 x 6.6, 5 10 to 49 1,840 2 x N/A MV x 4.4, 6 N/A 3,300 3 x Gaseeker GS4 Methane 0-10, CEA 6 x 6, to 50 1,200 6 x Instruments, Foxboro MIRAN 1Bx x 11, 28 5 to 40 17,100 x Company Table 4-3 (continued) Infrared, Electrochemical, and Solid State Analyzers Method 21 Criteria USA 1300 yes yes yes AIM yes* yes yes yes yes yes yes* See Comments. Infrared, Electrochemical, and Solid State Analyzers Maximum Dimensions USA 1300 Methane 0-50, X 2 dia, AIM 50 1,200 5 to Benzene 0-50, dia, to 50 2,200 5 x (mg/m 3) Inc. 43

56 Range Battery/Fuel (in.) and Temperature Price* Calibration Model Gas (ppmv) Life (hr) Weight (Ib) (Celsius) ($) Comments Manufacturer Tech, Inc Hexane 0-1, Gas 3.8 x 5.5, 8-12 to 49 1,300 7 x Hexane 0-2, x 3.8 x 5.5, 8-12 to 49 2, Gasurveyor 4 0-1, McNeil 3.8 x 4.1, to 50 1, x International base unit price 8/91. Approximate Comments. See Comments: Infrared. Internal library of approximately 115 compounds. Calibration ranges from 0-10 ppmv to 0-2,000 ppmv. Digital readout. Infrared 1. instrument. Range can be expanded to 0-100,000 ppmv with 10:1 dilution probe option. 2. Mercury vapor detector only. Digital readout. 3. Digital readout, data logging capabilities, software optional. 4. Digital readout with data logging capabilities. PC software optional. 5. Logarithmic LED scale, not defined enough at 95% for Method Analog meter, also reads 0-100% LEL combustibles. 7. Analog meter, also reads 0-100% LEL combustibles, 0-25% oxygen, ppmv H S, and ppmv CO 8. Digital readout, data logging system with integral bar code pen. 25,000 and 50,000 ppmv ranges available. 9. Electronically calibrated. 10. initial steps must be taken to document Several of a device that fails to meet Method 21 viability First, a laboratory program must requirements. response of monitoring instrument demonstrate compounds being measured. This response to be documented. second step is relating must response (i.e., screening value) to actual instrument to develop an instrument response concentrations screening value response curve must be curve. for entire screening value range and developed be adjusted to actual concentrations. Third, can program should be sufficiently well documented testing demonstrate how instrument will be used in to program. For example, if response time screening candidate instrument exceeds Method 21 of specification, test plan should reflect performance screening time at each potential leak point to be added Once this laboratory demonstration is screened. and screening value correction curve is completed screening can begin. established, screening begins, monitoring instrument Before be calibrated (U.S. EPA, 1988, p. 3-22). VOC must analyzer is assembled and started up according to zero gas into sample probe, and set introduce meter readout to zero. He or she n instrument introduce calibration gas into sample should and adjust instrument meter readout to probe, to calibration gas value. If meter correspond cannot be adjusted to proper value, a readout of instrument is indicated, and malfunction measures should be taken before corrective is used. operator's manual for each instrument might help determine cause of instrument Also, verifying that calib[ation gas malfunction. rated concentration of gas might be contains Procedure for Screening Equipment mechanics of screening operation outlined in Method 21 are summarized in following Reference (U.S. EPA, 1992a). operator places discussion inlet at surface of leak interface where probe could occur. ( leak interface is boundary leakage process fluid and atmosphere.) between must be perpendicular, not tangential, to leak probe so that inaccurate readings do not result. interface probe should be moved along interface n while instrument readout is observed. If periphery meter reading increases, operator moves slowly along interface where leakage is probe until maximum meter reading is obtained, indicated probe inlet should be left at this maximum reading for approximately two times instrument location (continued) Table 4-3 Infrared, Electrochemical, and Solid State Analyzers (continued) Maximum Dimensions 4320 Hexane 0-2, x 3.8 x 5.5, 8-10 to 40 <5,000 9 data that can be related to EPA's data providing using an organic vapor analyzer (OVA) collected instructions. After appropriate manufacturer's period, person performing test should warmup calibrated to methane. appropriate. documented so that screening values taken in field 4.3 Screening Protocols Calibration

57 time. screening value is maximum response reading. recorded instrument measurement might exceed scale instrument. For example, reading might of 10,000 ppmv when using an OVA analyzer. To exceed an emission estimate, se higher readings generate must be recorded. A dilution probe should be used also allow measurement of concentrations greater than to instrument's normal range. OVAcan be equipped a dilution probe that permits measurement of with up to 100,000 ppmv. Extending concentrations range also requires calibrating measurement avoided. A short piece of Teflon tubing be be used can a probe tip extender and snipped off as tip fouls. as areas with a noticeable particulate loading, this In can be packed with untreated fiberglass to act tubing as in place.) If a surface to be screened is obviously filter probe tip can be held just over surface to dirty, scooping up contaminants. While some fouling is avoid cleaning sintered steel filter probe tip unavoidable, least daily and side-pack filter weekly is at Normally, se filters can be cleaned recommended. rapping m lightly on a table top, but if deposits by wet and caked on, washing with an aqueous are of soap and alcohol is recommended. This solution also can be used to wash probe and solution line periodically. In addition, equipment transfer be blown dry before reuse. se general should can be used when screening equipment procedures as valves; flanges; pumps and compressors; such relief devices; and or potential sources of pressure leakage such as process drains, open-ended VOC lines, or valves. valves, most common leak source is at seal For stem and housing. To screen this source, between operator should place probe where stem packing gland, and move it around stem exits screening value is maximum circumference. reading. Also, probe should be placed at recorded packing gland take-up flange seat, and moved periphery. Valve housings of multipart along also should be. screened at surface of assemblies points where leaks could occur. Primary valve all points are illustrated in Figure 4-1. (See maintenance Figures 3-10 through 3-14 for additional also of flange-gasket interface, and circumference of Valve stem Figure 4-1. flange sampled. For screwed flanges, threaded interface also should be screened. Or connection of nonpermanent joints, such as threaded types should be sampled with a similar traverse. connections, Pumps and Compressors and compressors are screened.with a Pumps traverse at outer surface of circumferential or compressor shaft and seal interface where pump exits housing. If source is a rotating shaft, shaft probe inlet can be positioned within 1 cm of interface. If housing configuration shaft-seal a complete traverse of shaft periphery, all prevents joints on pump or compressor housing where or could occur. (Pump aqd compressor seal leakage and potential leak areas are illustrated in mechanisms 3-1 through 3-6.) Figures configuration of most pressure relief devices sampling at sealing seat. Because of ir prevents design and function, pressure relief devices must be Possible Packin gland to higher concentrations. instrument of probe with grease, dust, Fouling liquids should or Packing a filter. ( instrument also must be calibrated with this Primary valve malntenance points Valves as all accessible portions should be sampled, as well illustrations of various valve types.) Pressure Relief Devices Flanges flanges, probe should be placed at outer edge For 45

58 with extreme caution. se devices approached not be approached during process upsets, or at should times when y are likely to activate. Similarly, or should avoid interfering with working operators equipped with an enclosed extension or horn, devices probe inlet should be placed at approximately of exhaust area to atmosphere. Again, center probe should be placed in horn; personnel only screening should not place hands, conducting or any or body parts into horn. (See arms, 3-7 and 3-8 for illustration of screening points Figures a spring-loaded relief valve.) for opening is sufficient. For larger openings (e.g., a drain mouth), one must traverse perimeter of 6-inch opening and read concentration at center. even larger sources (e.g., a wash-up drain grate), a For of readings should be taken on about 6-inch grid For access door seals, probe inlet is placed centers. surface of door seal for a peripheral traverse. at all of se types of equipment, screening For Value Screening ID (ppmv) Process Unit Service Source Data Handling 4.4 han'dle screening data uniformly, data should be To on prepared data sheets. data collected recorded include: should place, IDs should be assigned consecutively as in source is screened. first source screened each assigned ID1, second source screened is is ID2, etc.) assigned Record screening value in ppmv. Source type (e.g., type of valve, pump, compressor, flange). Service (e.g., gas, light liquid, and heavy liquid). are classified, based on ir most volatile Liquids present at 20 weight percent or more. If component components have a total vapor pressure equal to greater than 0.04 psi at 20oC, material or classified as a heavy liquid. Classification is is upon actual process conditions, not ambient based Comments. If any explanation is required, it should noted. be example of a datasheet is given in Table 4-4 (U.S. An 1988, p. 3-23). In some cases, screening EPA, of device (e.g., seal disc and spring) parts screening pressure relief devices. For those when Date. Hydrocarbon detector type. Source identification (ID). (If permanent IDs are not Or Sources leaks from most or sources (e.g., process Fugitive seal system degassing vents, and accumulator drains, are emitted through a regularly shaped opening. vents) an opening is very small (e.g., sampling lines of less If center of than 1-inch diameter), a single reading in greater than or equal to 20 percent (containing by weight) is classified as a light liquid; if not, it VOCs conditions. maximum recorded value. concentration is Table 4.4 )le of a Datasheet (U.S. EPA, 1988 p. 3-23) Exam Hydrocarbon Type Detector Primary Metedal Comments Date 46

59 may need to be adjusted for RF, and values should be designed to accommodate extra datasheet Calibration Procedures for Quality 4.5 Assurance procedures must be used for quality control Calibration ensure high quality data that can be compared to to already gared by EPA. Each screening data must be calibrated before each use, and instrument morning and each afternoon. Also calibration each be checked periodically (during breaks in should testing schedule) to ensure that calibration has daily drifted. If reading is off by more than +5 percent not high standard, or +20 percent on low on instruments should be recalibrated. If standard, than one instrument is being used at a process more calibration readings must be calibrated for all unit, an NTIS number is cited in a reference, that When is available from: document Technical Information Service National Port Royal Road 5285 VA Springfield, Instrument Development, Inc. No date. Analytical ionization sources and a PIDmDifferent list of ionization potentials. Bulletin comprehensive AN-145. EPA. 1992a. U.S. Environmental Protection U.S. Method 21 evaluation for HON (90-ME- Agency. EPA-450/ Research Triangle Park, NC. 07). from U.S. EPA Information Center, Available EPA. 1992b. U.S. Environmental Protection U.S. Survey of portable analyzers for Agency. of gaseous fugitive emissions. EMTIC measurement File No. FNL-RPT.W51. Research Triangle BBS, NC. April 20. Available from Office of Park, and Development, Center for Research Research Information, Cincinnati, Environmental OH, EPA U.S. Environmental Protection Agency. U.S. techniques for fugitive VOC emission Inspection Student's manual. EPA-340/ a. sources: DC. September. Available from U.S. Washington, Information Center, Research Triangle Park, EPA NC, EPA U.S. Environmental Protection Agency. U.S. for generating unit-specific emission Protocols for equipment leaks of VOC and VHAP. estimates NTIS PB Research EPA-450/ Park, NC. October. Triangle EPA U.S. Environmental Protection Agency. U.S. instruments user's manual for monitoring Portable sources. EPA-340/ NTIS PB90- VOC EPA U.S. Environmental Protection Agency. U.S. VOC emissions in syntic organic Fugitive manufacturing industry. EPA-625/ chemicals Research Triangle Park, NC. December. p from Office of Research and Available Center for Environmental Research Development, potential VOC screening instruments. NTIS PB Research EPA-600/ Park, NC. November. Triangle EPA. 1981a. U.S. Environmental Protection U.S. Response factors of VOC analyzers at a Agency. reading of 10,000 ppmv for selected organic meter EPA-600/ NTIS PB81- compounds. Research Triangle Park, NC. September EPA. 1981b. U.S. Environmental Protection U.S. EPA U.S. Environmental Protection Agency. U.S. factors of VOC analyzers calibrated with Response for selected organic compounds. EPA-600/ methane NTIS PB Research Triangle columns for RF and corrected screening values. from se checks recorded. For example, readings should calibrate instruments before usage operators Washington, DC. June. pp instruments. Cincinnati, OH, Information, EPA U.S. Environmental Protection Agency. U.S. 4.6 References Evaluation of Response of portable VOC analyzers to Agency. mixtures. EPA-600/ NTIS PB81- chemical Research Triangle Park, NC. June. Research Triangle Park, NC, Park, NC. September. 47

60

61 5 Chapter and NESHAP Equipment Leak Records and Reports NSPS regulations is evaluation of reports and NESHAP examination of onsite records. Records must be to demonstrate compliance with maintained and to provide information for required regulations A discussion of recordkeeping standards reports. a description of content of reports required by and and NESHAP regulations is included in this NSPS Also included in appendices to this chapter chapter. Recordkeeping 5.1 of a facility's records is an important element of Review wher that facility is in compliance with determining standards (U.S. EPA, 1990a,b). NSPS and NESHAP leak regulations require maintenance of fugitive detailed records on site (see Section 2.2.4). extensive, to requirements. subject A list of equipment ID numbers for equipment for Uno detectable emissions." no designated emissions designation must be signed by detectable owner or operator and requires an annual test and a record of date of compliance required to comply with standards for devices relief devices in gas/vapor service. pressure A record of determination of process streams in service or in liquid service. gas/vapor A record of determination of percentage content benzene in process streams. of A list of ID numbers for pumps in light liquid service require weekly visual checks. that a closed-vent system and a control device are used to If fugitive emissions, records for this equipment control Detailed schematics, design specifications, and and instrumentation diagrams. piping Dates and descriptions of any changes in design specifications. A description of parameter(s) monitored to that a control device is operated and ensure conformance with design, and an of why that parameter was selected for explanation monitoring. Periods when closed-vent systems and control are not operated as designed, including devices system is an alternative for reducing emissions fluid pumps and compressors. If a dual mechanical seal from system with a barrier fluid system is must be recorded: 1) design criteria that information failure of seal system, barrier fluid indicates or both; 2) an explanation of choice of this system, criteria; and 3) documentation of any changes to design criteria and reasons for changes. records also must contain a list of ID numbers for that are designated as unsafe-to-monitor,-an valves for this designation, and plan for explanation with skip period provisions, a schedule of complying and a record of percent of valves found monitoring during each monitoring, period must be kept leaking file. on part of determining compliance with NSPS and A vital must include: are examples of acceptable report formats. maintained.in records that are required include: Specific A list of identification (ID) numbers for all equipment when a flare pilot light does not have a flame. periods Dates of startups and shutdowns of closed-vent and control devices. systems dual mechanical seal system that includes a A barrier used, following test, background level measured, compliance maximum instrument reading measured at and equipment. A list of equipment ID numbers for pressure relief A list of ID numbers for equipment in vacuum service. NESHAP fugitive leak regulations also require records: each valve. same records are required monitoring valves designated as difficult-to-monitor. For valves for 49

62 criteria allow a facility to be exempted from Certain or NESHAP requirements. If a facility claims NSPS an n it must maintain a log that contains exemption, data, and analyses to support its exemption information, each compliance monitoring test conducted, For a of results must be retained. This includes record compressors, valves, and closed-vent systems. pumps, monitoring for alternative standards also must be Any nonperiodic circumstances require compliance Or A pressure relief device must be monitored monitoring. 5 calendar days after a pressure release to within that no emissions are detectable. If confirm pump or a is in heavy liquid service, a pressure relief device valve in light liquid or heavy liquid service, or a flange is or be monitored within 5 days. If a leak is detected must repair is attempted, component must be and to determine if repair attempt monitored was Records must be kept of findings of all successful. monitoring tests. If a leak is detected, such must be identified as a leaking component by equipment after equipment has been repaired and removed successfully. tag may be removed from retested a however, only after it has been repaired and valve, for 2 successive months with no detected monitored leaks are detected, records on each leak must be When and maintained for 2 years. For each detected kept equipment ID number, instrument and leak, ID numbers, and date leak was operator must be recorded. date of each repair detected and an explanation of each method applied attempt be recorded. If leak is corrected, n should of successful repair should be entered in log. If date repair is unsuccessful, operator should record maximum instrument reading of monitoring that respective repair was above 10,000 ppmv. after Chapter 4 for more information on monitoring.) (See for delay is that repair could not be reason until a process shutdown, n person attempted made decision to delay repair must sign log. who process unit shutdowns occurred while leak If unrepaired, dates of se shutdowns also remained be recorded. Finally, expected date of must leaks. See Table E-4 in Appendix E for a delinquent form to use to record this information. sample Reporting requirements for sources subject to found in general provisions (40 CFR Part 60, are,a) and in each individual NSPS (U.S. EPA, Subpart Chemical Manufacturing Industry; Subpart Organic Leaks of VOC in Petroleum GGGmEquipment Subpart KKK--Equipment Leaks of VOC Refineries; Onshore Natural Gas Processing Plants; and from refer directly to Subpart VV for reporting standards recordkeeping requirements. NSPS reporting and recordkeeping requirements discussed in this and are those contained in general provisions chapter types of NSPS reports are required. NSPS Two Provisions (40 CFR Part 60, SubpartA, 60.7) General that any owner or operator subject to an mandate must provide written notification of date of NSPS or reconstruction within 30 days after work construction In addition to construction or reconstruction begins. general provisions require following: notification, A notification of anticipated date of initial startup an affected facility postmarked between 30 and 60 of before startup date. days A notification of actual date of initial startup of an facility within 15 days after startup. affected of any pollutant to which a standard applies, rate that change is specifically exempted. This unless shall be postmarked 60 days, or as soon notice as before change. practicable, Initial Semiannual Reports 5.2,1.1 require facilities to submit semiannual reports NSPSs 6 months after initial startup date, and beginning 6 months reafter. initial semiannual report every include an identification of process unit, must of valves in gas/vapor service or light liquid number light liquid service, and number of compressors. Valves, pumps, and that are designated as having no compressors emissions should not be included in detectable listed in initial semiannual report. An example totals an NSPS initial semiannual report is presented in of F. Appendix 5.2 Reporting declaration NSPS Standards NSPSs leak monitoring for pumps and valves, as well monthly annual no detectable emissions monitoring for as NSPSs for VOC equipment leaks include 1990a,b). W--Equipment Leaks of VOC in Syntic Subpart documented. DDDEquipment Leak Standards for Subpart Manufacturing Industry. All se NSPS Polymer or connector is suspected of leaking, this equipment and in Subpart W. an ID tag to leaking equipment. tag attaching be wearproof and readily visible. A tag may be must leak. A notification of any physical or operational change an existing facility that may increase emission to If a leak is not repaired within 15 calendar days of being detected, "repair delayed" should be entered in log, and reason for delay should be discussed. If service, number of pumps in successful repair of leak should be entered for se 5O

63 Semiannual Reports reports are required beginning 6 months after Semiannual initial semiannual report, and each 6 months se reports contain information on reafter. of LDAR programs. information required in results semiannual report begins with process unit which should coincide with identification identification, initial semiannual report. As discussed in Chapter in a facility must establish and follow a monitoring 4, for valves, pumps, and compressors. When a program is discovered, it must be repaired within 15 leak days, barring unavoidable circumstances. calendar report must document, on a monthly basis, semiannual total number of detected leaks and number of In each instance where a repair is delayed, period. should explain delay. If reason for report delay is that it n report should indicate why a shutdown, unit shutdown was technically infeasible during process during reporting period when process unit dates occurred. In addition, any revisions to items shutdowns in initial semiannual report should be reported and discussed. described example of one acceptable format for an NSPS An report is presented in Appendix G. semiannual of reports is not specified in regulations, and format number of variations are acceptable. NESHAP a Or Reporting Requirements reporting requirements contained in NSPS Or include two alternative standards for valves: regulations allowable percentage of valves leaking, and LDAR program. first alternative skip-period a 2.0 percent limitation as maximum specifies of valves leaking within a process unit, percent by an initial performance test and a determined of one performance test annually reafter. minimum second alternative standard specifies two skip- LDAR programs. Under this option, an owner or period can skip from monthly/quarterly monitoring to. operator frequent monitoring after completing a specified less of consecutive monitoring intervals with number of valves leaking equal to or less than 2.0 percentage Under first skip program, after two percent. quarterly periods with fewer than 2.0 consecutive of valves leaking, an owner or operator may percent than 2.0 percent of valves leaking, annual fewer may be adopted. This second program is monitoring Detection Period Quarterly Action 3.1 monitor no monitor yes monitor yes inspections following five consecutive quarters of maintaining Annual good performance level of 2.0 percent. a consecutive quarter below 2. 0 pement means three quarters of Fifth may be skipped. monitoring of leaks below 2.0 percent means three quarters of Percentage may be skipped. monitoring with eir of se alternative standards, a comply must be provided 90 days before imple- notification provisions. menting strategies would permit a se demonstrated it is meeting "good performance has to monitor valves annually, semiannually, or level" Using this approach, a plant could minimize quarterly. and capital costs to achieve good performance labor by developing and implementing its own LDAR level or installing valves with lower probabilities procedures Table 5-1. Illustration of Skip-Period Monitoring (U.S. EPA, 1983)* Quarterly Leak Leak Rate of Valves During Taken (monitor Good Performance Period (%) vs. skip) Level Achieved? monitor yes monitor yes monitor yes monitor yes 5** 7 skip 8 skip 2 this total that were not repaired in required 15-day 9 skip 3 could not be repaired until a process unit monitor no 4 report n should show reporting period monitor yes monitor yes monitor yes monitor yes 5** 16 skip 17 skip 2 18 skip 3 examples (presented later in appendices) report some additional report formats. illustrate monitor yes 4 20 skip 21 skip 2 22 skip monitor yes 4 of leaks above 2.0 percent means quarterly monitoring Pementage be reinstituted.. must plant that consistently to semiannual monitoring. Under second skip after five consecutive quarterly periods with program, illustrated in Table 5-1. If an owner or operator elects to 51

64 leaking. Compared to a standard based of an on percentage of valves leaking," where not "allowable good performance level would be achieving a of regulation, penalty under violation work practice" standard would be only "alternative a to routine quarterly monitoring. return general provisions of NSPS regulations require owner or operator submit a written report of that of any performance test to EPA. Asdiscussed in results 2, performance tests are required for no Chapter emissions equipment and valves complying detectable an alternative standard. y also may be required with closed-vent systems, control devices, and for means of emission limitation. Information equivalent be made available to EPA as necessary to must operating conditions during determine performance tests. In NSPSs are federal regulations, enforcement although may be delegated from EPA to states. authority Emission Standard for Vinyl Chloride; F--National J--Equipment Leaks (Fugitive Sources) of Subpart of an initial statement, and each subpart submission submission of semiannual reports. If a requires test shows that fewer than 2.0 percent of performance valves for a vinyl chloride process unit are leaking se results must be submitted, and n new a test must be conducted annually. performance implement and testing, recordkeeping, and reporting standards contained in applicable NESHAP; and requirements on equipment subject to regulation, information equipment ID numbers, process unit IDs for including source, and a description of type of equipment each a pump or a pipeline valve). Also, percent by (e.g., of VHAPs in fluid being handled by weight and state of fluid (i.e., gas/vapor equipment or must be included. Finally, initial report liquid) contain a description of chosen method of must and a schedule for subsequent reports. compliance facilities in existence on effective date of All NESHAP standards were required to submit an initial refore, all existing facilities subject to report. standards already should have above-referenced an initial report. All new plants are required to submitted an initial report with application for approval submit construction required by general provisions of of 61 (NESHAPs). Part facility must submit reports. se reafter, reports are for NESHAP compliance and semiannual similar to required NSPS semiannual reports. are must contain process unit IDs and following y information on a basis for each process unit: monthly number of valves, compressors, and pumps that leaking, number that were not repaired detected 15 days. within An explanation of why a repair was delayed. If for delay was that a process unit shutdown reason shutdowns during 6-month reporting period and unit discussion of any revisions to initial report. a of NESHAP semiannual reports are contained Examples Appendices E and H through J. regulations do not in uses its own format. following are noteworthy and among se reports: items an explanation of delay. Although pump with not repaired within required time period, was clearly explains history of problem report This history begins with initial leak detection pump. follows it through until a successful repair was and reported. in E-3 of Appendix E is addition/ an Contained Table that presents anor format for list deletion information describing equipment subject to required NESHAPs. in Appendix is a report of monitoring Contained difficult- and unsafe-to-monitor valves. This report of in Appendix J are examples of annual Presented no emissions testing of closed-vent systems detectable Semiannual Reports months after initial report, and each 6 months Six detected leaking. were Of those valves, compressors, and pumps that were addition, NSPS (Subpart VV) that owner or operator notify requires of schedule for initial performance Administrator least 30 days before conducting m. Finally, tests at is n would be submitted to state agencies Reports of to EPA. instead needed before repair, n an explanation must be why a process unit shutdown was infeasible. given report also must include dates of all process NESHAP Standards NESHAPs regulate equipment leaks: Subpart Three and Subpart VmEquipment Leaks (Fugitive Benzene; Sources). Each of se NESHAPs requires Emission format of reports; y only specify specify content requirements. Each facility develops minimum in Appendix E is an example report for a Included that was not repaired within 15-day limit pump Initial Reports 5.2,2.1 initial report must contain two portions: written a assertion stating that company will also documents a skip program for monitoring valves. and valves and updates of equipment ID information. 52

65 is case for NSPSs, NESHAPs allow 1) As of equipment subject to a no detectable designation limit rar than an LDAR standard, 2) an emissions standard based on allowable percentage alternative valves leaking, and 3) an alternative skip-period Of program. All three of se require performance LDAR along with closed-vent systems and control tests If a performance test was conducted within devices. reporting period, n results of test 6-month must be included in semiannual report. also per year beginning 6 months after submittal of twice initial report. initial NESHAP report also must a schedule verifying months when se contain reports will be submitted. source n semiannual abide by this schedule unless it is amended in must semiannual reports. subsequent an owner or operator of a facility wishes to comply If eir of alternative standards for valves (i.e., with allowable percentage of valves leaking or skip- LDAR program), he/she must provide notification period days before implementation of eir of se 90 programs. require an application for approval of construction/ not se circumstances are 1 a new source modification. construction of a process unit, or 3) all information of in initial report is contained in next required an NTIS number is cited in a reference, that When is available from: document Technical Information Service National Port Royal Road 5285 VA Springfield, EPA. 1990a. U.S. Environmental Protection U.S. Inspection techniques for fugitive VOC Agency. EPA-340/ a. Washington, DC. manual. Available from U.S. EPA Information September. Inspection techniques for fugitive VOC Agency. sources: Course module $380. Lecturer's emission EPA-340/ b. Washington, DC. manual. Available from U.S. EPA Information September. of volatile organic compound equipment leaks Control natural gas/gasoline processing plants. EPA- from NTIS PB Research Triangle 450/ NC. December. Park, 5.3 References emission soumes: Course module S380. semiannual NESHAP reports must be submitted Student's Research Triangle Park, NC, Center, EPA. 1990b. U.S. Environmental Protection U.S. Research Triangle Park, NC, Center, EPA U.S. Environmental Protection Agency. U.S. Certain circumstances described in regulations do complies with standards, 2) a new source is not part semiannual report. 53

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67 se data must be carefully and consistently data. and updated. Presented in this chapter are recorded and automated methods for maintaining manual required in an LDAR program. manual method data maintaining data on a collection of involves automated method tracks datasheets; Manual Data Management 6.1 manual method of data management entails regulations require each regulated facility to 6 Chapter Management Systems Data keep information for all affected equipment at following facility: method of compliance rest of this section, descriptions of required In data for portable monitoring detector Calibration be kept as referenced in EPA Reference Method must (see Appendix C). Even though this information 21 not-be required to be reported under NSPS might any LDAR program. As discussed in Chapter 4, of required Method 21 calibration data include RFs, precision, and response time. Documentation calibration RF and response time is required only once, prior to of detector in service. Normally, RF information placing provided by detector equipment manufacturer or is a published reference (see Section for a through If sample pumping system or flow discussion). of detector is altered so that configuration time changes, response time must be tested response again before furr use. If required, such a test could incorporated easily in procedure for documenting be precision. calibration to Method 21, demonstration of calibration According is required prior to placing a detector in precision and at 3-month intervals or next use, whichever service later. A datasheet for documenting calibration is is resented in Figure This datasheet precision space for recording an instrument ID number includes heading. To complete datasheet, data within entered in column 1, operator's initials in column are and referenc compound and its known 2, in columns 3 and 4. concentration evaluate calibration precision, three readings must To taken. At beginning of instrument performance be test, instrument is assembled and evaluation up according to manufacturer's instructions. warmed gas is introduced into instrument sample Zero and instrument meter readout is adjusted to probe, calibration gas is introduced, readout is zero. to correspond to calibration gas value, zero adjusted is introduced, and resultant reading is recorded in air 5. n, calibration gas is introduced and column column 6. After readings are recorded, in value of difference between known absolute and measured concentration is entered in concentration 7. Calibration precision is determined by column average algebraic difference between calculating meter readings and known value (entered in 8) and dividing this value by known column value. result is multiplied by 100 to calibration calibration precision as a percentage express in column 9) (40 CFR Part 60, Appendix A). An (entered described, instrument is with monitoring requirements of Complying leak standards generates large amounts of equipment information in a PC-based system. and updating datasheets, performing developing and recording all information by hand. calculations, Equipment ID numbers and process-unit descriptions Type of equipment (e.g., pumps, valves) Type of service (gas/vapor or liquid) primary material being transported in line measured concentration (after 30 seconds) is recorded information and suggested formats for datasheets to record appropriate information are presented Calibration Data and NESHAP standards, it must be maintained as part entry is presented in Figure 6-1; a blank copy example this datasheet is presented in Appendix K. of instrument calibration procedure must be performed beginning of each use of instrument. As at assembled and warmed up All figures are presented at end of this chapter. 55

68 manufacturer's instructions. Zero gas introduced, instrument readout meter is adjusted is zero, a calibration gas is introduced, and meter to is adjusted to correspond to calibration gas readout Once calibrated, a span check can be taken to value. verify that no "drift" of calibration has occurred. A span consists of introducing zero air followed by check gas to verify that instrument readout has calibration changed or drifted from set values. Span checks not be taken before shutting off an instrument in should for long periods of time (i.e., 4 to 6 hours). If operation instrument is shut off for any reason, such as to an (U.S. EPA, 1986). A datasheet for recording startup procedure is presented in Figure 6-2. calibration piece of equipment. best way to approach any each emissions monitoring program is to break fugitive a facility into smaller, more manageable units large to specific processes in facility--se relating are "process units." For example, each storage tank called a facility could be treated as a separate unit when in A complete set of forms for maintaining a monitoring system is presented in Appendix K. equipment equipment ID form for pumps, shown in Figure 6-3, An for definition of smaller units within facility allows that each unit has its own specific series of numbers so a three-digit prefix is established for each unit (i.e., in a facility). A number is assigned to count operation piece of equipment within a unit, and categories of each are grouped on individual ID sheets. Thus, equipment a equipment numbering system could be based potential a three'digit unit prefix and a four-digit equipment on number, which would generate numbers such specific 001 to 0002 (001 would be unit number, and 0002 as indicate second piece of equipment in that would Equipment ID numbers can be generated in any unit). that an affected facility determines logical; this is fashion an example format. ID numbers, however, merely a//of affected equipment, is available. detailing not specifically required by regulations, Although attachment of an ID number to each piece of permanent equipment is recommended. affected rest of information required to complete ID form is specified by regulations and is pump consistent with information required to a physical description of pump and its includes dates when equipment was put in location; and, if applicable, taken out of service; a service of type of service pump is in (liquid or description piece of equipment also should have its own Each monitoring form, similar to one for equipment (see Figure 6-4). information required to pumps pump monitoring form includes complete on condition of seal pot. When monitoring notes pumps, only measurement that should be standard is maximum concentration emitted from recorded equipment. For pumps subject to no detectable regulations, three measurements should be emissions ambient concentration of VOCs, maximum recorded: emitted from equipment, and concentration concentration ( difference between actual and ambient readings). maximum ID and monitoring forms for compressors Equipment presented in Appendix K. Because pumps and are are similar pieces of equipment from a compressors perspective, se forms are identical to monitoring for pumps. those equipment ID and monitoring forms for valves will depending on wher valve is unsafe- or vary For those valves that are not difficult-to-monitor. or difficult-to-monitor, forms are identical to unsafe- For valves that are or difficult-to-monitor, equipment ID and unsafeforms are different, reflecting alternate monitoring schedule required for such valves. monitoring.in Figure 6-5 is a table that can be used to Illustrated information for an unsafe- or difficult-to- record valve, which includes equipment ID monitor alternate schedule for each piece, an number, of why valve is unsafe- or difficult-to- explanation and operator's signature. monitor, ID and monitoring forms for flanges and Equipment relief devices are presented in Appendix K. pressure differ from or equipment in that y can Flanges comply with no detectable emissions must or be in vacuum service. standards Figure 6-6, an example format for a leak detection. In is presented. All of information that must be report according to primary material passing through pump gas); its concentration; method of compliance; and and signature of operator and any comments. change battery pack, it should be recalibrated after ID number, monitoring date, name of equipment operator, notes of any visual evidence of a leak, and Equipment Monitoring Information equipment monitoring system requires identifying and monitoring affected equipment associated tagging individual tanks. with paper-based those for pumps (see Appendix K). should be easily traceable for outside observers (e.g., personnel). ID numbers may be assigned regulatory blueprints, as long as an accurate set of prints, from with fugitive emissions only by means of comply 21 monitoring and vacuum service Method no detectable emissions option has been exclusion; from forms. Pressure relief devices eir removed be recorded summarized on recorded when a leak is detected is for or types of equipment. This information 56

69 including equipment ID number; operator's form, date leak was detected; and, most name; date leak was stopped, repairs importantly, were made, and documentation for any delays in that a leak is detected. Monitoring is required after which repair is attempted. resulting instrument each recording a series of repair efforts on a single report for a successful repair is accomplished. date of until repair (once accomplished) is entered on successful form, and this report is completed. If a new leak is report begun. format used for all of datasheets presented here just suggested and may be modified. Combining is datasheets into one LDAR notebook provides se complete list of all equipment affected by a and a single record tracing compliance regulations each piece of equipment. information required by of or regulatory agencies normally would have EPAand be transcribed into a summary format from se to records. source Automated Data Management 6.2 PC-based information management systems Several commercially available for managing information are by regulations. se systems are effective required offer many advantages over. manual approach and above, but y are also relatively expensive. presented major advantage of se systems is capability One gar compliance information in field on a PC, to n can be downloaded to a desktop PC at which location. anor an NTIS number is cited in a reference, that When is available from: document Port Royal Road 5285 VA Springfield, EPA U.S. Environmental Protection Agency. U.S. instruments user's manual for monitoring Portable sources. EPA-340/ NTIS PB90- VOC Washington, DC. June repair. separate report is kept for each piece of equipment for A is recorded in column 3, while a brief description reading repair effort is recorded in column 2. This allows of 6.3 Reference detected later on same piece of equipment, a new leak detection report is National Technical Information Service

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77 Developing Emission Estimates 7.1 estimates are developed to meet requirements Emission permitting and inventories and for various regulations, for Superfund Amendments and Reauthorization e.g., of 1986 (SARA). In determining compliance with Act of performance or evaluating effectiveness standards individual programs of emissions reduction, estimating of from a given source is a key element. While emissions dispersed fugitive emission sources can be widely more difficult (U.S. EPA, 1986a). somewhat in this chapter are five methodologies Described to use to develop unit-specific emission appropriate for equipment leaks of VOCs and VHAPSo estimates methods are average emission factor se leak/no-leak emission factor method; method; emission factor method; application of three-strata correlations; and development of new, site- EPA correlations (U.S. EPA, 1988). specific five methods require some data collection, All analysis, and/or statistical evaluation. five data in flowchart,.methods vary in rigorousness shown complexity. average factor method is least and methods require an accurate count of equipment All by type of equipment and by service. components basic approach is to apply EPA-developed most emission factors to equipment counts for average 7 Chapter Considerations Engineering of equipment components yields emission number per source type, and sum of emission rates rate Factor Emlsslon Service (kg/hrlsource)* Equipment Gas Valves liquid Light Heavy liquid seals Light liquid Pump liquid Heavy Compressor seals Gas/vapor Flanges All Open-ended lines All Sampling connections All emission sources, EPA used assessment studies leak equipment in petroleum refineries and SOCMI (U.S. of using portable OVAs, and mass emissions gared measured by enclosing individual pieces of were equipment in bags and measuring organic material in bags. se data permitted collected of leak rate/screening value correlations development emission factors for sources in petroleum and and SOCMI (U.S. EPA, 1980, 1981a). Leak refineries value correlations and emission factors rate/screening generated in se studies for valves in gas/vapor were in SOCMI. Leak rate/screening value service also were generated for light liquid valves correlations light liquid pumps in SOCMI; industry average and factors were not developed. emission Table 7-1. product of emission factor and for all source types provides unit-specific emission estimates. Table 7-1. Average Emission Factors for Fugltlve Emissions for process emission sources is a relatively testing procedure, estimating emissions from straightforward Pressure relief seals Gas/vapor To convert to Ib/hr, multiply value by and options available for collecting methodologies analyzing data are shown in Figure 7-1. As and To develop emission factors for individual equipment and demanding, and developing site-specific complex is most complex and demanding. correlations EPA, 1980a,b). In se studies =screening" data were product of each methodology is an emissions end for equipment leaks organized by type of inventory and by service (i.e., light liquid, gas, or heavy equipment liquid) Use of EPA's Average Emission Factors unit. EPA's average emission factors are shown in Text in this chapter is based on U.S. EPA, 1988, except as noted. 65

78 equipment Count components composite Count survey screening factor (response optional) adjustment components for each Bag type and service equipment Figure 7-1. individual Develop correlations statistically Compare existing conditions to correlations equal? new correlation Apply composite total and - Inventory screening value Adjust OVNmethane format to Strategy for estimating emissions from equipment leaks. average emission Apply and composite factors leak/no-leak Apply factors and emission composite total emissions three strata Apply and composite emission EPNOVA correlations Apply screening values to default zero above value screening default zero emission Apply to screening values rate default below screening values zero Composite total (by type and service) total emissions Inventory Inventory Inventory total emissions Inventory emissions Yes Are emissions 66

79 factor method, which allows adjustment to emission unit conditions and operation. This method individual screening of all equipment to be included in require screening should be conducted using a inventory; OVA. Equipment that is dangerous to screen portable be omitted from set of equipment components can be screened; emission rates of dangerous-to-screed to can be estimated instead using EPA's equipment and nonleaking emission factors, as shown in leaking 7-2. Table Pump seals Compressor seals Open-ended lines and Nonleaking Emission Factors for Leaking Emissions (kg/hrlsource) Fugitive Gas* liquid Light leaking and nonleaking emission factors for valves in service are based upon emission factors determined for gas/vapor ethylene, cumene, and vinyl acetate units during Maintenance Study. SOCMI leaking emission factor is assumed equal to nonleaking factor since computed leaking emission factor ( emission was less than nonleaking emission factor. kg/hr/source) emission factor reflects existing control level of 60 percent in industry; control is achieved through use of barrier found equipment can be considered difficult-to- Insulated equipment, and decision to remove monitor to facilitate screening is left to individual insulation If insulation is not removed, insulated judgment. is assumed to leak at same rate as component a similar uninsulated component. would flanges, a reduced number of components can be For by screening a sample number of flanges until screened 95 percent confidence interval is achieved (U.S. EPA, a pp. E-1 and E-2). In compiling screening values 1988, use in this technique (or any of those that follow), an for can be applied to adjust screening values RF for chemical in line to a known measured for instrument. standard leak/no-leak method is based on assumption of two emission rates and two populations of only components: sources that leak (with equipment concentrations greater than or equal to screening ppmv) and sources that do not leak (with 10,000 concentrations less than 10,000 ppmv). This screening assumes that when a group of sources leaks, approach average, it leaks at a certain emission rate. Similarly, on a group, nonleaking sources average a certain mass as rate. Thus, overall emission estimate for a emission of emission sources consists of two population source emissions and nonleaking components--leaking in Table 7-2 are leaking and nonleaking Presented factors determined by EPA for equipment emission generated using 1)emission factors calculated were empirical screening distribution data and leak rate/ from mass emissions associated with leaking sources. of detailed procedure for generating leaking and and also is described in Emission Factors for 1982) Leaks of VOC and HAP (U.S. EPA, 1986a, Equipment 3-12 through 3-21). pp. application of leak/no-leak method for estimating An is shown in following example for a emissions chemical process unit. Presented in Table hypotical are data necessary for applying this method to 7-3 hypotical unit. second column contains of sources in process unit, by source type. number third column contains number of sources with screening values greater than or equal to leaking sources). percentage of sources (i.e., is shown in fourth column. emissions leaking for this hypotical process unit n can be estimates using applicable leaking and nonleaking computed Table 7-3. For example, 3 of 47 pump seals beneath light liquid service were found to be leaking. Using in method, following emission estimate is leak/no,leak for pumps in light liquid service: generated kg/hr/source (6.4%) (93.6%)]0.01 [0.437 kg/hr/source emission estimate per source for pumps in light service can be computed by dividing unit- liquid specific emission estimate by equipment count. Leak/No-Leak Approach leak/no-leak method is a refinement of average and all remaining methods discussed in this chapter Table 7-2. source emissions. Nonleaking (<10,000 Leaking (10,000 ppmv) leaks. se leaking and nonleaking emission factors ppmv) Emission Factor Service Equipment Emission Factor Valves value correlations, 2) leak frequencies screening with emission factors, and 3) percent associated Heavy liquid ** liquid Light liquid Heavy emission factors is published in Fugitive nonleaking Sources of Organic Compounds (U.S. EPA, Emission Gas Pressure relief Gas valves All Flanges All gas valves in 10,000 ppmv reservoir/vent-to-flare or or seal leakage capture fluid/degassing system. emission factors shown in Table 7-2 and equation 67

80 Estimate of "Uncontrolled" Fugitive Emissions for e Hypotical Case Source Number Screened Number Leaking Percent Leaking (kg/hr/sourca) (Mg/yr) seals Pump liquid 47 3 Light Heavy liquid Valves Gas/vapor liquid 1, Light Heavy liquid relief valves Pressure 31 Gas/vapor connections 70 Sampling 2, Flanges on values u,. Table 7-2, using EE [LEF Based PCL + NLEF x (100-PCL)]/100 where: x emission estimate (per source) EE emission factor leaking emission factor nonleaking hypotical process unit is assumed to be in continuous This so it operation, operate for fewer hours per year, so annual emissions would be prorated may account for hours equipment contained chemical. to Table 7-3 contains annual emissions by source type, for hypotical unit. estimates, this example illustrates how total VOC emissions While source type are calculated, a similar procedure per can used to estimate emissions for be particular species in a where light liquid in a process contains 20 case percent of Compound A. emission estimate weight Compound A for light liquid pumps is computed by for weight percent (in this case, 20 percent) to applying emission estimate generated: (0.20)(0.039 kg/hr) kg/hr. Anor example can be illustrated in case if light liquid contains only 80 hypotical percent VOC and Compound A accounts for 20 weight by weight of VOC. emission estimate percent Compound A for light liquid pumps would be for Application of Stratified Emission Factors of leak/no-leak approach that refinement uses emission factors. leak/no-leak method is stratified on two emission rates and two populations (i.e., based and nonleaking sources). stratified emission leaking method divides nonleaking factor into two sources screening value ranges. discrete operates for 8,760 hours per year. Batch or campaign processes values in EPA SOCMI data base Screening are widely from 0 ppmv to distributed than 100,000 more and mass emissions are distributed ppmv, stratified emission factor method correspondingly. this distribution into discrete intervals to segments for different ranges of screening values. account generated from data gared during previous EPA been se stratified emission factors represent studies. leak rates measured during fugitive emissions ir development incorporated statistical testing. used by EPA in developing or emission methods emission factor for each discrete interval, factors. equipment type and service, is presented in Table 74. by method requires all equipment screening (except This dangerous-to-screen equipment) to be conducted in for with EPA reference methods. All screening accordance must be recorded according to applicable values n, as with leak/no-leak method, ranges. of appropriate emission factor and product of components in each screening value number range Table 7-3. Annual** Computed Emission Estimate* Emlselons lines Open-ended seals 4 0 Compressor LEF NLEF PCL percent of sources found leaking last column in line. For example, consider this same hypotical ranges are used: following 0-1,000 ppmv 1,001-10,000 ppmv Over 10,000 ppmv factors for each screening value range have Emission computed as: (0.2)(0.8)(0.039 kg/hr) kg/hr. Anor method of generating emission estimates is a 68

81 Factors (kg/hrlsource) for Emission Value Ranges (ppmv) Screening Source Service 0-1,000 1,001-10,000 Over 10,000 Gas/vapor Valves liquid Light Heavy liquid seals Light liquid Pump liquid Heavy Gas/vapor Pressure devices relief emission rate for that value range and yields source total emission rate is sum of all emission type. for each value range and source type. Illustrated rates Table 7-5 is manner in which stratified emission in Leak Rate/Screening Value Correlations Estimate of Fugitive Emissions Using Stratified Emission Factors for a Hypotical Case correlations offer a continuous function Mamatical entire range of screening values instead of over intervals. EPA has published correlations discrete screening values to mass emissions rates (U.S. relating 1980b, 1981a). As shown in Table 7-6, correlations EPA, been developed to apply to four equipment types have taken using Method 21 with an instrument measurements to methane (see Appendix C for information calibrated Method 21). Screening value measurements used on se published correlations should use a similar with For example, if a threshold limit value (TLV) format. calibrated to hexane is used to gar instrument data, data must be transformed to screening measurements gared using an OVA, represent to methane, before using published calibrated If a detector fails to meet Method 21 correlations. or published transformations are not specifications an instrument response curve must be available, to relate screening values to actual developed in appropriate format (OVNmethane). concentrations screening value correction curve should be This in laboratory before detector is used developed correction factor that can be applied to Method Anor and non-method 21 instruments is RF. For many 21 Emission Estimate Computed Per Source Per Source** Number Source Screened 0-1,000 1,001-10,000 Over 10,000 Type,* (kg/hr) (kg/hr/source) Valves liquid 1,180 1, Light seals Pump liquid Light seals Compressor Gas/vapor relief devices Pressure Gas/vapor Based on emission factors from Table 7-4: EE (NL x SEF1) + (NL2x SEF2) +... where: NL, number leaking in first range (0-1,000), number leaking in second NL (1,001-10,000)i etc. etc. range SEF etc. SEF stratified emission factor for first range, stratified em ssion factor for second range, etc. 2, 2, Computed emission estimate per source computed emission estimate per source type/number screened Stratified Emission Factors for Equipment Leaks Table 7-4. and services. EPA's correlations are based upon OVA Gas/vapor Compressor seals All Flanges, connections All Open-ended lines in field. factor approach should be implemented. compounds, instrument response is nonlinear with Table 7-5. Number of Sources Screened (ppmv) Heavy liquid Heavy liquid Flanges 2,880 2, Open-ended lines EE emission estimate 69

82 Prediction Equations for Nonmethane Leak Rate for Valves, Flanges, and Pump Seals in SOCMI Process Source Type Instrument Least-Squares Equation Pairs Coefficient (r) Valves* service OVA NMLK 1.68 (10 "5) (MXOVA) '693 Gas Light liquid service OVA NMLK 3.74 (10-4) (MXOVA) ' Flanges** OVA NMLK (10 "5) (MXOVA) 'e Pump Seals* OVA NMLK (i0 5) (MXOVA) 'sgs U.S. EPA, 1981b. *Source: U.S. EPA, 1980d. Source: Ib/hr; units might have to be changed for repong purposes. method, a single-point RF adjustment at no-leak definition of 10,000 ppmv is adequate. To use leak required, and a for nonlinear response must be made. This correction be accomplished in laboratory by generating a can curve. A number of EPA publications address response factor issues in greater detail (U.S. EPA, correction 1986b). 1981c,d; in flowchart in Figure 7-1 is a separate Depicted of "zero" screening values. function treatment correlation of leak rate and screening describing becomes discontinuous for zero and near-zero value and correlation functior mamatically values, zero emissions for zero readings on predicts instrument. EPA's data show this prediction to portable incorrect, however. Mass emissions have been be from equipment showing no screening measured above zero. se higher measured concentration are related to detector accuracy. For emissions of correlation, EPA derived a "default zero" end value (8 ppmv) and an associated mass screening for screening values between zero default zero reading. default zero values and emission rates shown in Table 7-7 were derived and mass emissions data gared in chemical from and published leak rate/screening value plants emission factors should be applied to equipment se screening between 0 and 200 ppmv, but components correlations should be applied to all published concentrations above 200 ppmv. total screening Deviation Standard Estimate of Screening Emission Rate Equipment, Value (ppmv) (kg/hrlsource) Type/Service Valves, gas adding that total to total estimates generated and correlations. An alternative methodology for using unit-specific default zero emission rates is generating in U.S. EPA (1988) and CMA (1989). presented facility may develop its own correlations for its process A if leak rates are statistically different from EPA's units following steps should be taken to generate rates. emission estimate using unit-specific correlations: an Gar mass emission data and calculate mass 1. rate (leak rate). emission Apply leak rate/screening value correlations to 4. screening data. empirical following paragraphs present details of each step. Table 7-6. Number of Data Correlation NMLK nonmethane leak rate (Ib/hr) MXOVA maximum screening value (ppmv)--ova instrument NMLK is given in Table 7-7. Default Zero Values and Emission Rates increasing screening value. In terms of basic leak/ Default Zero Zero Screening Value correlations, however, best estimate of screening concentration over entire range is Valves, light liquid Flanges and all or Pumps components by totaling emissions estimates for all "default zeroes" 7.1,5 Unit-Specific Correlations a case where mass emissions corresponded example, a screening value of <200 ppmv could not be to because accuracy limit of detector quantified 200 ppmv. To handle this discontinuity at low was emission rate 2. Develop leak rate value correlation. Develop statistical considerations of leak rate/screening 3. correlations. value correlations. 5. Predict emissions. emissions estimate for equipment leaks is generated 7O

83 process unit is screened for all source types, After components in each source type can.be selected to measure mass emission rate. bagged selected for mass emission measurement components be rescreened at time of bagging. should emission rate determined by bagging and mass value n are used to validate rescreening of EPA's correlations to process unit. application leak rate/screening value correlations are based EPA data gared using an OVA instrument calibrated on used, n screening value must be adjusted are oretical or empirical correction factors) to be (using data collection. To check fit of EPA-published of to a particular process unit, as few as four equations measurements of a particular source type in a leak-rate service could be adequate. If new equations particular leak rate/screening data, detecting differences of correlations with fewer than 30 data pairs is between Fewer data pairs are acceptable, however, if difficult. statistical goal still can be achieved. a hypotical process unit with a large Consider of sources with screening values well population over range of 0 to 100,000+ ppmv. To distributed statistically valid leak-rate/screening value develop.mass emissions data must be collected from correlations, sources that have screening values distributed individual entire range. For each source type (e.g., valves, over and service (e.g., gas, light liquid), a random pumps) PPt. n 20 (or all, whichever is less) of 100,000 screed at 100,000.ppmv should be bagged. sources six sources, not available in a particular screening If range, ational sources from nearest range value should be tea If screening values greater than ppmv are not found in process, following 10,000 groups can be used: five screen less than 1,000 ppmv. unit a statistical 'determination is made that emission If are within 50 percent of mean value and estimates percent confidence can be achieved with fewer 95 Number of Leak-Rate Total Measurements , ,001-10, , , >100, leak-rate/screening value correlations can be values, Least-squares regression analyses should generated. performed for each source type/service, regressing be logarithm of nonmethane leak rate on of screening concentration, according to logarithm following equation: (leak rate) B0 + B1 Log (screening concentration) Log where: parameters model intervals should be calculated for Confidence ppmv ppmv 301-1,000 ppmv 1,001-3,000 ppmv 3,001-10,000 ppmv groupings can be developed if all sources in Similar with methane. If or instruments or calibration,gases to values measured using an OVA calibrated equivalent methane prior to any comparisons to EPA with 30 data pairs, bagging strategies shown in. than 7-8 are recommended. Table Components yielding instrument readings equations. saturation point of detector must be above to quantify emission rate. bagged amount of bagging should depend on objective Begging Strategies Table 7-8. Velue Range Screening (ppmv) required, at least 30 leak-rate measurements should are obtained. statistical goal is to generate estimates be are within 50 percent of mean value with 95 that confidence. Because of inherent variability pement groupings and recommended number of sources se guidelines based on field experience in measuring are rates and developing leak-rate/screening value leak Or source selection strategies can be equations. an appropriate rationale is given. used if appropriate mass emission data and screening With of six soumes should be chosen for bagging sample each of following screening value ranges: from ppmv = ppmv 10t-1,000 1,('-10,000 ppmv 10,00.100,000 ppmv >100,0 ppmv maxir,m response of screening instrument is If Bo, B1 equation, and a scale-bias correction factor is estimated to transform equation in log scale back required original units. Bagged sources whose screening to are known to be above 100,000 ppmv, but whose values 71