11/26/2014 1:58 PM. First Revision No. 3-NFPA [ Chapter 2 ]

Transcription

1 of 37 11/26/2014 1:58 PM First Revision No. 3-NFPA [ Chapter 2 ] Chapter 2 Referenced Publications 2.1 General. The documents or portions thereof listed in this chapter are referenced within this recommended practice and should be considered part of the recommendations of this document. 2.2 NFPA Publications. National Fire Protection Association, 1 Batterymarch Park, Quincy, MA NFPA 30, Flammable and Combustible Liquids Code, edition. NFPA 33, Standard for Spray Application Using Flammable or Combustible Materials, edition. NFPA 34, Standard for Dipping, Coating, and Printing Processes Using Flammable or Combustible Liquids, edition. NFPA 35, Standard for the Manufacture of Organic Coatings, edition. NFPA 36, Standard for Solvent Extraction Plants, edition. NFPA 45, Standard on Fire Protection for Laboratories Using Chemicals, edition. NFPA 55, Compressed Gases and Cryogenic Fluids Code, edition. NFPA 58, Liquefied Petroleum Gas Code, edition. NFPA 59A, Standard for the Production, Storage, and Handling of Liquefied Natural Gas (LNG), edition. NFPA 70, National Electrical Code, edition. 2.3 Other Publications ANSI Publications. American National Standards Institute, Inc., 25 West 43rd Street, 4th Floor, New York, NY ANSI/ISA-RP , Recommended Practice for Portable Electronic Products Suitable for Use in Class I and II, Division 2, Class I, Zone 2 and Class III, Division 1 and 2 Hazardous (Classified) Locations, API Publications. American Petroleum Institute, 1220 L Street, NW, Washington, DC API RP 500, Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1 and Division 2, (Reaffirmed, November 2002.) 3rd edition, 2008 API RP 505, Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, and Zone 2, 2002, reaffirmed ASHRAE Publications. American Society of Heating, Refrigeration and Air-Conditioning Engineers, Inc., 1791 Tullie Circle NE, Atlanta, GA ASHRAE 15, Safety Code Standard for Mechanical Refrigeration Systems, ASTM Publications. ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA ASTM D323, Standard Method of Test for Vapor Pressure of Petroleum Products (Reid Method), 2008 (2014) CGA Publications. Compressed Gas Association, 4221 Walney Road, 5th Floor George Carter Way, Suite 103, Chantilly, VA ANSI/ CGA G2.1, Safety Requirements for the Storage and Handling of Anhydrous Ammonia, IEC Publications. International Electrotechnical Commission, 3, rue de Varembé, P.O. Box 131, CH-1211 Geneva 20, Switzerland. IEC TR , Electrical apparatus for explosive gas atmosphere Part 20: Data for Flammable gaes and vapors, relating to the use of electrical apparatus, , Explosive atmospheres Part 20-1: Material characteristics for gas and vapor classification Test methods and data, 2012.

2 of 37 11/26/2014 1:58 PM ISA Publications. The International Society of Automation, 67 T.W. Alexander Drive, P.O. Box 12277, Research Triangle Park, NC ISA-RP , Standard for Portable Electronic Products Suitable for Use in Class I and II, Division 2, Class I Zone 2 and Class III, DIivision 1 and 2 Hazardous (Classified) Locations, Other Publications. Merriam-Webster s Collegiate Dictionary, 11th edition, Merriam-Webster, Inc., Springfield, MA, References for Extracts in Recommendations Sections. NFPA 30, Flammable and Combustible Liquids Code, edition. NFPA 59A, Standard for the Production, Storage, and Handling of Liquefied Natural Gas (LNG), edition. NFPA 70, National Electrical Code, edition. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 09:28:47 EDT 2014 Committee Statement Committee Statement: Response Message: Current editions referenced, updated titles of IEC and ISA standards, and eliminated the ANSI section due to standard development by IEC. ASHRAE 34 is not referenced in NFPA 497. Public Input No. 5-NFPA [Section No ] Public Input No. 12-NFPA [Chapter 2] Public Input No. 20-NFPA [Section No ]

3 of 37 11/26/2014 1:58 PM First Revision No. 19-NFPA [ Section No ] Combustible Liquid. Any liquid that has a closed-cup flash point at or above 100 F (37.8 C), as determined by the test procedures and apparatus set forth in Section 4.4 of NFPA 30, Flammable and Combustible Liquids Code. Combustible liquids are classified according to Section 4.3 of NFPA 30 in accordance with the following: (1) Class II Liquid Any liquid that has a flash point at or above 100 F (37.8 C) and below 140 F (60 C); (2) Class III Liquid Any liquid that has a flash point at or above 140 F (60 C); (a) Class IIIA Liquid Any liquid that has a flash point at or above 140 F (60 C), but below 200 F (93 C); (b) Class IIIB Liquid Any liquid that has a flash point at or above 200 F (93 C). [30, ] Class II Liquid. Any liquid that has a flash point at or above 100 F (37.8 C) and below 140 F (60 C). [ 30: 4.3.2(1)] Class III Liquid. Any liquid that has a flash point at or above 140 F (60 C). [ 30: 4.3.2(2)] Class IIIA Liquid. Any liquid that has a flash point at or above 140 F (60 C), but below 200 F (93 C). [ 30: 4.3.2(2)(a)] Class IIIB Liquid. Any liquid that has a flash point at or above 200 F (93 C). [ 30: 4.3.2(2)(b)] Submitter Information Verification Submitter Full Name: Eric Nette Organization: National Fire Protection Assoc Street Address: City: State: Zip: Submittal Date: Mon Oct 27 16:09:30 EDT 2014 Committee Statement Committee Statement: Definition revised to coincide with changes to NFPA 30. Response Message:

4 of 37 11/26/2014 1:58 PM First Revision No. 20-NFPA [ Section No ] Flammable Liquid. Any liquid that has a closed-cup flash point below 100 F (37.8 C), as determined by the test procedures and apparatus set forth in Section 4.4 of NFPA 30, Flammable and Combustible Liquids Code, and a Reid vapor pressure that does not exceed an absolute pressure of 40 psi (276 kpa) at 100 F (37.8 C), as determined by ASTM D323, Standard Test Method for Vapor Pressure of Petroleum Products (Reid Method). Flammable liquids are classified according to Section 4.3 of NFPA 30 as Class I liquids and further subclassified in accordance with the following: (1) Class IA Liquid Any liquid that has a flash point below 73 F (22.8 C) and boiling point below 100 F (37.8 C); (2) Class IB Liquid Any liquid that has a flash point below 73 F (22.8 C) and boiling point at or above 100 F (37.8 C); (3) Class IC Liquid Any liquid that has a flash point at or above 73 F (22.8 C), but below 100 F (37.8 C). [30, ] Class I Liquid. Flammable liquids, as defined in and of NFPA 30, Flammable and Combustible Liquids Code, shall be classified as Class I liquids and shall be further subclassified in accordance with Sections through : [ 30, 2012] Class IA Liquid. Any liquid that has a flash point below 73 F (22.8 C) and a boiling point below 100 F (37.8 C) [ 30: 4.3.1(1)] Class IB Liquid. Any liquid that has a flash point below 73 F (22.8 C) and a boiling point at or above 100 F (37.8 C) [ 30: 4.3.1(2)] Class IC Liquid. Any liquid that has a flash point at or above 73 F (22.8 C), but below 100 F (37.8 C) [ 30: 4.3.1(3)] Submitter Information Verification Submitter Full Name: Eric Nette Organization: National Fire Protection Assoc Street Address: City: State: Zip: Submittal Date: Mon Oct 27 16:10:45 EDT 2014 Committee Statement Committee Statement: Definition revised to coincide with changes to NFPA 30. Response Message:

5 of 37 11/26/2014 1:58 PM First Revision No. 15-NFPA [ Section No ] 4.1.2* In a Class I hazardous (classified) location, the combustible material present is a flammable gas, flammable liquid produced vapor, or combustible liquid produced vapor mixed with air that could burn or explode. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Fri Sep 19 11:03:54 EDT 2014 Committee Statement Committee Statement: The current text if read literally conflicts with the stated conditions of the combustible material groups by addressing only flammable gas or vapor. The revised text contains the complete description and agrees with the material Group terms. Response Message: Public Input No. 15-NFPA [Section No ]

6 of 37 11/26/2014 1:58 PM First Revision No. 7-NFPA [ Sections 4.1.3, 4.1.4, 4.1.5, 4.1.6, ] Class I is further subdivided into either Class I, Division 1 or Class I, Division 2; or Class I, Zone 0, Zone 1, or Zone 2 as detailed in through Class I, Division 1. A Class I, Division 1 location is a location In which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors can exist under normal operating conditions, or In which ignitible concentrations of such flammable gases, flammable liquid produced vapors, or combustible liquids above their flash points may exist frequently because of repair or maintenance operations or because of leakage, or In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. [ 70: 500.5(B)(1)] See FR Class I, Division 2. A Class I, Division 2 location is a location In which volatile flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems or in case of abnormal operation of equipment, or In which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors are normally prevented by positive mechanical ventilation and which might become hazardous through failure or abnormal operation of the ventilating equipment, or That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors above their flash points might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 500.5(B)(2)] Class I, Zone 0. A Class I, Zone 0 location is a location in which Ignitible concentrations of flammable gases or vapors are present continuously, or Ignitible concentrations of flammable gases or vapors are present for long periods of time. [ 70: 505.5(B)(1)] Class I, Zone 1. A Class I, Zone 1 location is a location In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 505.5(B)(2)]

7 of 37 11/26/2014 1:58 PM Class I, Zone 2. A Class I, Zone 2 location is a location In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and, if they do occur, will exist only for a short period; or In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 505.5(B)(3)] The intent of Articles 500 and 505 of the NEC is to prevent combustible material from being ignited by electrical equipment and wiring systems Electrical installations within hazardous (classified) locations can use various protection techniques. No single protection technique is best in all respects for all types of equipment used in a chemical plant Explosionproof enclosures, pressurized equipment, and intrinsically safe circuits are applicable to both Division 1 and Division 2 locations Nonincendive equipment is permitted in Division 2 locations Portable electronic products (PEPs) meeting the requirements for PEP-1 or PEP-2 of ANSI/ISA-RP Recommended Practice for Portable Electronic Products Suitable for Use in Class I and II, Division 2, Class I, Zone 2, and Class III, Division 1 and 2 Hazardous (Classified) Locations, are considered suitable for use in Division 2 and Zone 2 locations Nonsparking electrical equipment and other less restrictive equipment, as specified in the NEC, are permitted in Division 2 locations Factors such as corrosion, weather, maintenance, equipment standardization and interchangeability, and possible process changes or expansion frequently dictate the use of special enclosures or installations for electrical systems. However, such factors are outside the scope of this recommended practice, which is concerned entirely with the proper application of electrical equipment to avoid ignition of combustible materials For the purpose of this recommended practice, areas not classified as Class I, Division 1; Class I, Division 2: or as Class I, Zone 0, Zone 1, or Zone 2, are unclassified areas. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 14:09:28 EDT 2014 Committee Statement Committee Statement: Response Message: These sections address Classification of Class I locations and not Classification of combustible materials. See FR-5 (PI-18).

8 of 37 11/26/2014 1:58 PM Public Input No. 16-NFPA [Sections 4.1.3, 4.1.4, 4.1.5, 4.1.6, 4.1.7]

9 of 37 11/26/2014 1:58 PM First Revision No. 4-NFPA [ Section No ] 4.4.2*

10 0 of 37 11/26/2014 1:58 PM An alphabetical listing of selected combustible materials, with their group classification and relevant physical properties, is provided in Table Table Selected Chemicals Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio MESG (mm) Acetaldehyde C d I IIA Acetic Acid D d II IIA Acetic Acid- tert-butyl Ester D II Acetic Anhydride D II IIA 1.23 Acetone D d I IIA Acetone Cyanohydrin D IIIA Acetonitrile D I IIA 1.50 Acetylene A d GAS IIC Acrolein (Inhibited) B(C) d I IIB 0.13 Acrylic Acid D II IIB 0.86 Acrylonitrile D d I IIB Adiponitrile D IIIA Allyl Alcohol C d I IIB 0.84 Allyl Chloride D I IIA Allyl Glycidyl Ether B(C) e II Alpha-Methyl Styrene D II n-amyl Acetate D I IIA 1.02 sec-amyl Acetate D I IIA Ammonia D d,f GAS IIA Aniline D IIIA IIA Benzene D d I IIA Benzyl Chloride D IIIA Bromopropyne D I n-butane D d,g GAS IIA ,3-Butadiene B(D) d,e GAS IIB Butanol D d I IIA 0.91 Butyl alcohol (s) (butanol-2) D d I IIA Butylamine D GAS IIA 1.13 Butylene D I IIA 0.94 n-butyraldehyde C d I IIA 0.92 n-butyl Acetate D d I IIA sec-butyl Acetate D II tert-butyl Acetate D II n-butyl Acrylate (Inhibited) D II IIB 0.88 n-butyl Glycidyl Ether B(C) e II n-butyl Formal C IIIA 34.3 Butyl Mercaptan C I Butyl-2-Propenoate D II

11 1 of 37 11/26/2014 1:58 PM Chemical para tert-butyl Toluene D IIIA n-butyric Acid D d IIIA Carbon Disulfide d,h I IIC Carbon Monoxide C d GAS IIB 0.54 Chloroacetaldehyde C IIIA Chlorobenzene D I Chloro-1- Nitropropane C IIIA Chloroprene D GAS Cresol D IIIA Crotonaldehyde C d I IIB 0.81 Cumene D I IIA 1.05 Cyclohexane D I IIA Cyclohexanol D IIIA IIA Cyclohexanone D II IIA 0.98 Cyclohexene D I IIA 0.97 Cyclopropane D d I IIA p-cymene D II IIA Decene D II n-decaldehyde C IIIA 0.09 n-decanol D IIIA Decyl Alcohol D IIIA Diacetone Alcohol D IIIA Di-Isobutylene D d I Di-Isobutyl Ketone D II o-dichlorobenzene D IIIA IIA 1,4-Dichloro-2,3 Epoxybutane D d I IIA ,1-Dichloroethane D I IIA ,2-Dichloroethylene D I IIA ,1-Dichloro-1- Nitroethane C IIIA ,3-Dichloropropene D I Dicyclopentadiene C I IIA 0.91 Diethylamine C d I IIA 1.15 Diethylaminoethanol C IIIA IIA Diethyl Benzene D II Diethyl Ether (Ethyl Ether) Diethylene Glycol Monobutyl Ether Diethylene Glycol Monomethyl Ether CAS No. Class I Division Group Typea Flash Point ( C) C d I IIB C IIIA C IIIA n-n-dimethyl Aniline C IIIA Dimethyl Formamide D II IIA 1.08 Dimethyl Sulfate D IIIA Dimethylamine C GAS IIA AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio MESG (mm)

12 2 of 37 11/26/2014 1:58 PM Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio MESG (mm) 2,2-Dimethylbutane D g I ,3-Dimethylbutane D g I 396 3,3-Dimethylheptane D g I ,3-Dimethylhexane D g I 438 2,3-Dimethylpentane D g I Di-N-Propylamine C I IIA ,4-Dioxane C d I IIB Dipentene D II IIA 1.18 Dipropylene Glycol Methyl Ether C IIIA Diisopropylamine C GAS IIA 1.02 Dodecene D IIIA Epichlorohydrin C d I Ethane D d GAS IIA Ethanol D d I IIA Ethylamine D d I Ethylene C d GAS IIB Ethylenediamine D d I Ethylenimine C d I Ethylene Chlorohydrin D IIIA Ethylene Dichloride D d I Ethylene Glycol Monoethyl Ether Acetate Ethylene Glycol Monobutyl Ether Acetate Ethylene Glycol Monobutyl Ether Ethylene Glycol Monoethyl Ether Ethylene Glycol Monomethyl Ether C II IIA C IIIA C IIIA C II D II Ethylene Oxide B(C) d,e I IIB Ethylhexaldehyde C II Ethylhexanol D IIIA Ethylhexyl Acrylate D IIIA Ethyl Acetate D d I IIA Ethyl Acrylate (Inhibited) D d I IIA 0.86 Ethyl Alcohol D d I IIA Ethyl Sec-Amyl Ketone D II 59 Ethyl Benzene D I Ethyl Butanol D II

13 3 of 37 11/26/2014 1:58 PM Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Ethyl Butyl Ketone D II Ethyl Chloride D GAS Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio Ethyl Formate D GAS IIA 0.94 Ethyl Mercaptan C d I IIB n-ethyl Morpholine C I Ethyl-3-Propyl Acrolein C IIIA Ethyl Silicate D II 7.2 Formaldehyde (Gas) B GAS IIB 0.57 Formic Acid D II IIA 1.86 Fuel Oil D Fuel Oil 2 Fuel Oil 6 II or IIIA k 38 72k II or IIIA k 52 96k 257 IIIA or IIIB k k Furfural C IIIA Furfuryl Alcohol C IIIA Gasoline D d I n-heptane D d I IIA n-heptene D g I n-hexane D d,g I IIA Hexanol D IIIA IIA Hexanone D I Hexene D I sec-hexyl Acetate D II Hydrazine C II Hydrogen B d GAS IIC Hydrogen Cyanide C d GAS IIB 0.80 Hydrogen Selenide C I 7793 Hydrogen Sulfide C d GAS IIB Isoamyl Acetate D I Isoamyl Alcohol D II IIA 1.02 Isobutane D g GAS IIA 0.95 Isobutyl Acetate D d I Isobutyl Acrylate D I Isobutyl Alcohol D d I IIA Isobutyraldehyde C GAS IIA 0.92 Isodecaldehyde C IIIA Isohexane D g IIA 1.00 Isopentane D g Isooctyl Aldehyde C II Isophorone D MESG (mm)

14 4 of 37 11/26/2014 1:58 PM Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio MESG (mm) Isoprene D d I Isopropyl Acetate D I Isopropyl Ether D d I IIA Isopropyl Glycidyl Ether C I Isopropylamine D GAS Kerosene D II IIA Liquefied Petroleum Gas D I 405 Mesityl Oxide D d I Methane D d GAS IIA Methanol D d I IIA Methyl Acetate D GAS IIA Methyl Acrylate D GAS IIB Methyl Alcohol D d I IIA 0.91 Methyl Amyl Alcohol D II IIA 1.01 Methyl Chloride D GAS IIA 1.00 Methyl Ether C d GAS IIB Methyl Ethyl Ketone D d I IIB Methyl Formal C d I Methyl Formate D GAS IIA Methylhexane D g I 280 Methyl Isobutyl Ketone D d I Methyl Isocyanate D GAS IIA 1.21 Methyl Mercaptan C GAS Methyl Methacrylate D I IIA 0.95 Methyl N-Amyl Ketone D II Methyl Tertiary Butyl Ether D I Methyloctane Methylpropane D g I Methyl-1-Propanol D d I IIA 0.98 Methyl-2-Propanol D d I Methyl-5-Ethyl Pyridine D Methylacetylene C d I Methylacetylene- Propadiene C I IIB 0.74 Methylal C I Methylamine D GAS IIA Methylbutane D g Methylcyclohexane D I Methylcyclohexanol D Methycyclohexanone D II 3.9

15 5 of 37 11/26/2014 1:58 PM Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio MESG (mm) 2-Methylheptane D g Methylhexane D g Methylpentane D g Methylpropane D g I Methyl-1-Propanol D d I Methyl-2-Propanol D d I Methyloctane D g Methyloctane D g Methyloctane D g Monoethanolamine D IIA Monoisopropanolamine D Monomethyl Aniline C Monomethyl Hydrazine C I Morpholine C d II IIA 0.95 Naphtha (Coal Tar) D II IIA Naphtha (Petroleum) D d,i I IIA Neopentane D g Nitrobenzene D IIA 0.94 Nitroethane C I IIB 0.87 Nitromethane C I IIA Nitropropane C I IIB Nitropropane C d I n-nonane D g I IIA Nonene D I Nonyl Alcohol D IIA n-octane D d,g I IIA 0.94 Octene D I n-octyl Alcohol D IIA 1.05 n-pentane D d,g I IIA Pentanol D d I IIA Pentanone D I IIA Pentene D I Pentene D I Pentyl Acetate D I Phenylhydrazine D Process Gas > 30% H 2 B j GAS Propane D d GAS IIA Propanol D d I IIA Propanol D d I IIA Propiolactone D

16 6 of 37 11/26/2014 1:58 PM Chemical CAS No. Class I Division Group Typea Flash Point ( C) AIT ( C) %LFL %UFL Vapor Density (Air = 1) Vapor Pressure b (mm Hg) Class I Zone Group c MIE (mj) MIC Ratio Propionaldehyde C I IIB 0.86 Propionic Acid D II IIA 1.10 Propionic Anhydride D n-propyl Acetate D I IIA 1.05 n-propyl Ether C d I Propyl Nitrate B d I Propylene D d GAS IIA Propylene Dichloride D I IIA 1.32 Propylene Oxide B(C) d,e I IIB Pyridine D d I IIA Styrene D d I IIA 1.21 Tetrahydrofuran C d I IIB Tetrahydronaphthalene D IIIA Tetramethyl Lead C II Toluene D d I IIA 0.24 n-tridecene D IIIA Triethylamine C d I IIA Triethylbenzene D ,2,3-Trimethylbutane D g 442 2,2,4-Trimethylbutane D g 407 2,2,3-Trimethylpentane D g 396 2,2,4-Trimethylpentane D g 415 IIA ,3,3-Trimethylpentane D g 425 Tripropylamine D II IIA 1.13 Turpentine D I n-undecene D IIIA Unsymmetrical Dimethyl Hydrazine C d I IIB 0.85 Valeraldehyde C I Vinyl Acetate D d I IIA Vinyl Chloride D d GAS IIA 0.96 Vinyl Toluene D Vinylidene Chloride D I IIA 3.91 Xylene D d I IIA Xylidine C IIIA a Type is used to designate if the material is a gas, flammable liquid, or combustible liquid. (See and ) MESG (mm) b Vapor pressure reflected in units of mm Hg at 77 F 25 C (25 C 77 F ) unless stated otherwise. c Class I, Zone Groups are based on 1996 IEC TR , Electrical apparatus for explosive gas atmospheres Part 20: -1, Explosive atmospheres Part 20-1: Data Material characteristics for flammable gases and vapours, relating to the use of electrical apparatus gas and vapor classification Test methods and data, which contains additional data on MESG and group classifications. d Material has been classified by test.

17 7 of 37 11/26/2014 1:58 PM e Where all conduit runs into explosionproof equipment are provided with explosionproof seals installed within 18 in. 450 mm (450 mm 18 in. ) of the enclosure, equipment for the group classification shown in parentheses is permitted. f For classification of areas involving ammonia, see ASHRAE 15, Safety Code Standard for Mechanical Refrigeration Systems, and ANSI/ CGA G2.1, Safety Requirements for the Storage and Handling of Anhydrous Ammonia. g Commercial grades of aliphatic hydrocarbon solvents are mixtures of several isomers of the same chemical formula (or molecular weight). The autoignition temperatures (AIT) of the individual isomers are significantly different. The electrical equipment should be suitable for the AIT of the solvent mixture. (See A ) h Certain chemicals have characteristics that require safeguards beyond those required for any of the above groups. Carbon disulfide is one of these chemicals because of its low autoignition temperature and the small joint clearance necessary to arrest its flame propagation. i Petroleum naphtha is a saturated hydrocarbon mixture whose boiling range is 68 F to 275 F 20 C to 135 C (68 F to 275 F 20 C to 135 C ). It is also known as benzine, ligroin, petroleum ether, and naphtha. j Fuel and process gas mixtures found by test not to present hazards similar to those of hydrogen may be grouped based on the test results. k Liquid type and flash point vary due to regional blending differences Where the MESG and MIC ratio values result in different group classifications, notwithstanding other applicable data, the more restrictive group classification should be applied. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 11:52:57 EDT 2014 Committee Statement Committee Statement: Response Message: The committee provided clarification of the action to be taken when MESG and MIC ratio data support different Group classifications. The committee continues to support the application of data to support area classification. Public Input No. 11-NFPA [Section No ]

18 8 of 37 11/26/2014 1:58 PM First Revision No. 5-NFPA [ New Section after 5.1 ] 5.1 National Electrical Code (NEC) Class I is subdivided into either Class I, Division 1 or Class I, Division 2; or Class I, Zone 0, Zone 1, or Zone Class I, Division 1. A Class I, Division 1 location is a location See FR-7 (1) In which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors can exist under normal operating conditions, or (2) In which ignitible concentrations of such flammable gases, flammable liquid produced vapors, or combustible liquids above their flash points may exist frequently because of repair or maintenance operations or because of leakage, or (3) In which breakdown or faulty operation of equipment or processes might release ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors and might also cause simultaneous failure of electrical equipment in such a way as to directly cause the electrical equipment to become a source of ignition. [ 70: 500.5(B)(1)] Class I, Division 2. A Class I, Division 2 location is a location (1) In which volatile flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors are handled, processed, or used, but in which the liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in case of accidental rupture or breakdown of such containers or systems or in case of abnormal operation of equipment, or (2) In which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors are normally prevented by positive mechanical ventilation and which might become hazardous through failure or abnormal operation of the ventilating equipment, or (3) That is adjacent to a Class I, Division 1 location, and to which ignitible concentrations of flammable gases, flammable liquid produced vapors, or combustible liquid produced vapors above their flash points might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 500.5(B)(2)] Class I, Zone 0. A Class I, Zone 0 location is a location in which (1) Ignitible concentrations of flammable gases or vapors are present continuously, or (2) Ignitible concentrations of flammable gases or vapors are present for long periods of time. [ 70: 505.5(B)(1)] Class I, Zone 1. A Class I, Zone 1 location is a location (1) In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or (2) In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or (3) In which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitible concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or (4) That is adjacent to a Class I, Zone 0 location from which ignitible concentrations of vapors could be communicated, unless communication is prevented by adequate positive pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 505.5(B)(2)]

19 9 of 37 11/26/2014 1:58 PM Class I, Zone 2. A Class I, Zone 2 location is a location (1) In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and, if they do occur, will exist only for a short period; or (2) In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or (3) In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation but which may become hazardous as a result of failure or abnormal operation of the ventilation equipment; or (4) That is adjacent to a Class I, Zone 1 location, from which ignitible concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided. [ 70: 505.5(B)(3)] For the purpose of this recommended practice, areas not classified as Class I, Division 1; Class I, Division 2: or as Class I, Zone 0, Zone 1, or Zone 2, are unclassified areas The intent of Articles 500 and 505 of the NEC is to prevent combustible material from being ignited by electrical equipment and wiring systems In a Class I area, the following three conditions must be satisfied for the combustible material to be ignited by the electrical installation: (1) A combustible material must be present. (2) It must be mixed with air in the proportions required to produce an ignitible mixture. (3) There must be a release of sufficient energy to ignite the mixture Electrical installations within hazardous (classified) locations can use various protection techniques. No single protection technique is best in all respects for all types of equipment used in a chemical plant Explosionproof enclosures, pressurized equipment, and intrinsically safe circuits are applicable to both Division 1 and Division 2 locations Nonincendive equipment is permitted in Division 2 locations * Portable electronic products (PEPs) meeting the requirements for PEP-1 or PEP-2 of ISA-RP , Standard for Portable Electronic Products Suitable for Use in Class I and II, Division 2, Class I, Zone 2 and Class III, Division 1 and 2 Hazardous (Classified) Locations, are considered suitable for use in Division 2 and Zone 2 locations Nonsparking electrical equipment and other less restrictive equipment, as specified in the NEC, are permitted in Division 2 locations Factors such as corrosion, weather, maintenance, equipment standardization and interchangeability, and possible process changes or expansion frequently dictate the use of special enclosures or installations for electrical systems. However, such factors are outside the scope of this recommended practice, which is concerned entirely with the proper application of electrical equipment to avoid ignition of combustible materials. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State:

20 0 of 37 11/26/2014 1:58 PM Zip: Submittal Date: Tue Sep 16 13:58:00 EDT 2014 Committee Statement Committee Statement: Material which was located under the section dealing with Material Group has been properly relocated under this section dealing with Classification. Aside from organization, there was no intent to introduce new information which was not otherwise found in 497 or the NEC. Response Message: Public Input No. 18-NFPA [New Section after 5.1]

21 1 of 37 11/26/2014 1:58 PM First Revision No. 8-NFPA [ New Section after ] 5.9.5* Step 5 Documentation. Documentation should be prepared for all areas designated as hazardous (classified) locations. Such documentation should be available to those authorized to design, install, inspect, maintain, or operate electrical equipment and process equipment at the location Documentation should be current and include the following, at a minimum, for all areas that are classified: (1) The Class (2) The Division or Zone (3) The name of combustible material(s) and its respective material group and autoignition temperature or appropriate design T-code It might also be desirable to include the maximum permissible operating temperature or temperature range for electrical equipment in the area. Supplemental Information File Name 497_A docx Description Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 14:12:48 EDT 2014 Committee Statement Committee Statement: Documentation is an extremely important aspect of hazardous area classification and while implied in a number of sections within this practice, documentation is not specifically called out. This new section addresses this important need. Response Message: Public Input No. 19-NFPA [New Section after 5.8.4]

22 A A means of documenting hazardous (classified) area locations is with a plan view of the hazardous area classification location depicting the following: Formatted: Font: Bold a(1) The major process or other equipment and components that may could be the release source of flammable gases or vapors, or flammable liquids to the atmosphere; (2b) Tthe boundaries of the various area classifications; c(3) Identify tthe evaluated locations that were determined to be unclassified and (4d) Oother information (Le.e.g., information on ventilation) necessary to properly classify a location. Elevations or sections are often used where different classifications apply at varying elevations. This documentation serves as a record of the original hazardous area classifications and as a guide when future additions or revisions to the facility are considered. Commented [PJ1]: Eric: Re: A.5.8.5: Is information on ventilation in item (4) an example? If so, should read: e.g., information on ventilation. Commented [NE2]: e.g. would be correct.

23 2 of 37 11/26/2014 1:58 PM First Revision No. 11-NFPA [ Section No. 5.9 [Excluding any Sub-Sections] ]

24 3 of 37 11/26/2014 1:58 PM Most diagrams in Section 5.10 and Section 5.11 include tables of suggested applicability and use check marks to show the ranges of process equipment size, pressure, and flow rates. (See Table ) Unless otherwise stated, these diagrams assume that the material being handled is a flammable liquid. Table 5.10 provides a summary of where each diagram is intended to apply. Class I, Division diagrams include Figure (a) through Figure Table 5.10 Matrix of Diagrams Versus Material/Property/Application Figure Number VD Indoor, for Class I Special Condition VD > 1 < Cryogenic Indoor Poor Outdoor Above At Refer to Table Grade 1 Grade Division Zone Ventilation Size Pressure Flow 5.9.1(a) (a) X X X S/M S/M S/M 5.9.1(b) (b) X X X S/M S/M S/M 5.9.1(c) (c) X X X S/M S/M S/M 5.9.1(d) (d) X X X S/M S/M S/M 5.9.1(e) (e) X X X S/M S/M S/M 5.9.1(f) (f) X X X S/M S/M S/M 5.9.1(g) (g) X X X L M/L L 5.9.1(h) (h) X X X L M/L L 5.9.1(i) (i) X X X M/L L M/L 5.9.1(j) (j) X X X M/L L M/L 5.9.1(k) (k) X X X X S/M S/M S/M 5.9.1(l) (l) X X X X M/L M/L M/L 5.9.1(m) (m) X X X X S/M S/M S/M 5.9.1(n) (n) X X X X S/M S/M S/M 5.9.2(a) (a) X X X X S/M M/H S/M 5.9.2(b) (b) X X X X S/M M/H S/M 5.9.3(a) (a) Product dryer FL X X X 5.9.3(b) (b) Filter press FL X X 5.9.4(a) (a) Storage tank FL X X M/L L M/L 5.9.4(b) 5.9.4(c) 5.9.4(d) 5.9.4(e) (b) (c) (d) (e) Tank car loading Tank car loading Tank truck loading Tank car loading/tank truck loading Tank car loading/tank truck loading Drum filling station Emergency basin 5.9.8(a) (a) Liquid H 2 storage 5.9.8(b) FL X X FL X X X FL X X X FL X X X FL X X X FL X X X FL X X X X X X X X X (b) Gaseous H 2 storage X X X X X 5.9.9(a) (a) Compressor shelter X X X X

25 4 of 37 11/26/2014 1:58 PM Figure Number Indoor, for Class I Special VD VD > 1 Cryogenic Indoor Condition < 1 Poor Outdoor Above At Refer to Table Grade Grade Division Zone Ventilation Size Pressure Flow 5.9.9(b) (b) Compressor shelter X X X X (a) (a) Cryogenic storage X X X X (b) (b) Cryogenic storage X X X X (c) (c) Cryogenic storage X X X X LNG X X X LNG X X X LNG X Marine terminal FL/LFG X X X FL: Flammable liquid. LFG: Liquefied flammable gas. LNG: Liquefied natural gas. X: Diagram applies. L: Large. M: Moderate. S: Small. H: High. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 15:24:52 EDT 2014 Committee Statement Committee Statement: The table was updated to include consistency with NFPA 59A and FR-9. Response Message:

26 5 of 37 11/26/2014 1:58 PM First Revision No. 17-NFPA [ Section No ] Storage Tanks for Cryogenic Liquids. [See Figure (a), Figure (b), and Figure (c).] Figure (a) Tank for the Storage of Cryogenic and Other Cold Liquefied Flammable Gases. Dike height less than distance from container to dike (H < x). [59A: Figure A (a) (b).] Figure (b) Tank for the Storage of Cryogenic and Other Cold Liquefied Flammable Gases. Dike height greater than distance from container to dike (H > x). [59A: Figure A (b) (c) ] Figure (c) Tank for the Storage of Cryogenic and Other Cold Liquefied Flammable Gases. Container with liquid level below grade or top of dike. [59A: Figure A (c) (d).] Submitter Information Verification Submitter Full Name: Eric Nette Organization: National Fire Protection Assoc Street Address: City: State: Zip: Submittal Date: Thu Oct 16 15:47:01 EDT 2014 Committee Statement Committee Statement: Extracts were updated for the most recent edition of NFPA 59A. Response Message:

27 6 of 37 11/26/2014 1:58 PM First Revision No. 18-NFPA [ Section No ] Routinely Operating Bleeds Liquefied Natural Gas or Other Cryogenic Flammable Gas. (See Figure ) Figure Classified Zones around Liquefied Natural Gas Routinely Operating Bleeds, Drips, Vents, and Drains Both Outdoors, at or above Above Grade, and Indoors, in an Adequately Ventilated Building. This diagram also applies to other cold liquefied flammable gases. (Source: Table of NFPA 59A.) Submitter Information Verification Submitter Full Name: Eric Nette Organization: National Fire Protection Assoc Street Address: City: State: Zip: Submittal Date: Thu Oct 16 15:52:32 EDT 2014 Committee Statement Committee Statement: Improperly referenced instead of out of NFPA 59A. Response Message:

28 7 of 37 11/26/2014 1:58 PM First Revision No. 9-NFPA [ Section No ] Marine Terminal Flammable Liquids. (See Figure ) Figure Classified Locations at a Marine Terminal Handling Flammable Liquids or Liquefied Flammable Gases ; Includes the Area Around the Stored Position of Loading Arms and Hoses. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 14:51:26 EDT 2014 Committee Statement Committee Statement: The text in the figure and the title were updated to include consistency with NFPA 59A. Response Message:

29 8 of 37 11/26/2014 1:58 PM First Revision No. 13-NFPA [ Section No ]

30 9 of 37 11/26/2014 1:58 PM Indoor and Outdoor Process Flammable Liquids.

31 0 of 37 11/26/2014 1:58 PM [See Figure (a) through Figure (n).] Figure (a) Leakage Located Outdoors, at Grade. The material being handled is a flammable liquid. Figure (b) Leakage Located Outdoors, above Above Grade. The material being handled is a flammable liquid. Figure (c) Leakage Located Indoors, at Floor Level. Adequate ventilation is provided. The material being handled is a flammable liquid. Figure (d) Leakage Located Indoors, above Above Floor Level. Adequate ventilation is provided. The material being handled is a flammable liquid. Figure (e) Leakage Located Indoors, at Floor Level, Adjacent to an Opening in an Exterior Wall. Adequate ventilation is provided. The material being handled is a flammable liquid.

32 1 of 37 11/26/2014 1:58 PM Figure (f) Leakage Located Indoors, at Floor Level, Adjacent to an Opening in an Exterior Wall. Ventilation is not adequate. The material being handled is a flammable liquid. Figure (g) Leakage Located Outdoors, at Grade. The material being handled is a flammable liquid. Figure (h) Leakage Located Outdoors, above Above Grade. The material being handled is a flammable liquid. Figure (i) Leakage Located Indoors, Adjacent to an Opening in an Exterior Wall. Ventilation is not adequate. The material being handled is a flammable liquid.

33 2 of 37 11/26/2014 1:58 PM Figure (j) Leakage Located Indoors, Adjacent to an Opening in an Exterior Wall. Adequate ventilation is provided. The material being handled is a flammable liquid. Figure (k) Leakage, Located Both at Grade and above Above Grade, in an Outdoor Process Area. The material being handled is a flammable liquid. Figure (l) Multiple Sources of Leakage, Located Both At at Grade and Above Grade, in an Outdoor Process Area. The material being handled is a flammable liquid. Figure (m) Multiple Sources of Leakage, Located Both at and above Above Grade, in an Outdoor Process Area. The material being handled is a flammable liquid.

34 3 of 37 11/26/2014 1:58 PM Figure (n) Multiple Sources of Leakage, Located Both at and above Above Floor Level, in an Adequately Ventilated Building. The material being handled is a flammable liquid. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 16:20:13 EDT 2014 Committee Statement Committee Statement: There is an error in figure (n) with improper measurements and hatch marks. Response Message:

35 4 of 37 11/26/2014 1:58 PM First Revision No. 10-NFPA [ Section No ] Marine Terminal Flammable Liquids. (See Figure ) Figure Classified Locations at a Marine Terminal Handling Flammable Liquids or Liquefied Flammable Gases ; Includes the Area Around the Stored Position of Loading Arms and Hoses. Submitter Information Verification Submitter Full Name: [ Not Specified ] Organization: [ Not Specified ] Street Address: City: State: Zip: Submittal Date: Tue Sep 16 15:21:56 EDT 2014 Committee Statement Committee Statement: The text in the figure and the title were updated to include consistency with NFPA 59A. Response Message: