Lab Ventilation Safety & Energy Efficiency. Agenda & Objectives

Transcription

1 Lab Ventilation Safety & Energy Efficiency Methods to Achieve Safe and Energy Efficient Laboratory Ventilation Systems Thomas C. Smith Agenda & Objectives Introduction Laboratory Safety & Risks Demand for Ventilation Airflow Specifications Commissioning & Routine Tests Lab Hoods Lab Environment Lab Ventilation Systems Lab Ventilation Optimization Copyright

2 Goal: High Performance Laboratories Chemistry Labs Radiological Labs Nanotechnology Labs Biology Labs (high containment) Animal Vivariums Cleanrooms Safe Compliant with Codes & Standards Productive (Flexible) Energy Efficient Sustainable Risk & Potential for Adverse Health Effects Inhalation Hazards Type of Airborne Materials Toxicity Generation Rate & Concentration Duration of Exposure Physical Hazards Dermal Exposure Fire & Explosion Dose = Concentration x Duration Copyright

3 Primary Objective: Lab Safety and Personnel Protection Laboratory Hoods & Ventilation Systems DUCTS FILTER STACK FAN Proper Performance = Protection Proper Performance = Compliance Operation 60% Utility Costs Cost = $ 3 to $ 9 per cfm-yr ROOF AIR SUPPLY Lab hoods are the primary means LAB OFFICE THINK SAFETY of protecting lab personnel Copyright

4 Evaluating Fume Hood Safety ANSI/ASHRAE 110 Method of Testing Performance of Laboratory Fume Hoods PWGSC - MD15128 Laboratory Fume Hoods Determine Operating Conditions Hood and Lab Inspection Face Velocity Measurements Cross Draft Velocity Tests VAV Response and Stability Tracer Gas Ejector Mannequin Tracer Gas Detector Computer & DAQ Determine Performance (Containment ) Flow Visualization Smoke Tests Tracer Gas Containment Tests Face Velocity Probe Cross Draft Probe Methods to Evaluate Containment Performance and Ensure Safe Hoods Laboratory Hood Safety & Performance ECT, Inc. has conducted more than 30,000 ASHRAE 110 Tracer Gas Containment Tests Test Results Demonstrate > 15% Failure Primary Factors Affecting Performance Hood design - 20% Lab Design System Operation 55% Work practices - 25% Copyright

5 Know the Operating Limits Utility Costs for Laboratories & Fume Hoods One of the highest energy users by building type Average Annual Energy Cost for a Lab Building = $700,000 (100,000 ft 2 ) Laboratory Buildings have 10 to 250 fume hoods Average Annual Energy Cost for a Traditional Fume Hood = $5,000 Equivalent to Three 2500 sq. ft. Houses Estimated lifetime cost of operation $150,000 (30 yrs) Building Type Average Utility Cost Commercial/Office $ 1 / ft 2 Lab Energy Use Lights 10% Hospital $ 3 / ft 2 Laboratory $ 7 / ft 2 Specialty Labs & Cleanrooms $ 15 / ft 2 HVAC 60% 30% Plug/Misc. Copyright

6 ANSI/AIHA Z American National Standard for Laboratory Ventilation Newly Revised & Published September 2012 Minimum Requirements and Best Practices Protect People Ensure Dependable Operation Operate Energy Efficient Labs Recommendations & Specifications for New and Renovated Laboratories Hood Design & Operation Laboratory Design Ventilation System Design Commissioning and Routine Testing Work Practices and Training Preventative Maintenance Airflow Specifications for Laboratories Minimum Flow and Range of Modulation Required to Meet the Functional Requirements of the Lab Safety Hood Exhaust Flow Laboratory Pressurization Dilution (ACH) Comfort & Productivity Temperature Demand for Ventilation Humidity Occupancy & Utilization Copyright

7 Bench-Top Types of Laboratory Fume Hoods Traditional Bypass Low Velocity / High Performance VAV Restricted Bypass Distillation Floor Mounted (Walk-in) Fume Hood Operation and Specifications Sash Opening Configuration 100% Full Open Design Opening User Opening Average Face Velocity 100 fpm (0.51 m/s) Traditional 60 fpm (0.3 m/s) High Performance Exhaust Flow CAV VAV o Minimum Flow ( ACH) Copyright

8 Bench-Top Fume Hood Vertical Sash Opening Horizontal Sash Opening Laboratory Hood Test Methods ASHRAE or ASHRAE EPA NIH PWGSC Copyright

9 Laboratory Hood and System Tests Pre-Purchase Factory Acceptance Tests Mock Up Tests As Manufactured Tests Commissioning Tests As Installed Tests ASHRAE 110 Hood Tests Lab Environment Tests System Operating Mode Tests Routine Performance Tests As Used Tests Maintenance Management Continuous Commissioning Fume Hood Tests ANSI/ASHRAE 110 Method of Testing Performance of Laboratory Fume Hoods Operating Tests Hood and Lab Inspection Face Velocity Measurements Cross Draft Velocity Tests VAV Response and Stability Performance (Containment ) Tests Flow Visualization Smoke Tests Tracer Gas Containment Tests Copyright

10 Hood Survey and Inspection Monitor Baffle Panels Access Panel Sash Airfoil Cabinet Cross Draft Measurement Non-directional Anemometer Determine Imaginary Hood Zone Identify Sources of Cross Draft Measure Velocity of Cross Draft Determine Direction with Smoke Left Top View Center Right Vertical Horizontal Design opening Perpendicular Mid-point Front View Side View Copyright

11 A1 A2 A3 B1 B2 B3 C1 C2 C3 D1 D2 D3 E1 E2 E3 Velocity - fpm Safe. Dependable and Energy Efficient Laboratories April 2014 Face Velocity Test Divide Opening Into Grids < 1 ft 2 Mount Anemometer Probe at Grid Center Record readings (~1 per second) Calculate Overall Average & Variation Face Velocity Traverse Qe 6" Vertical Sash H Vf 6" 6" W ows Face Velocity Grids Columns A B C D E 1 2 Probe Stand Number of rows and columns depends on opening Height (H) and Width (W) H - Height from work surface to sash W - Interior opening width in plane of sash Vfavg = sum (Vfmean)/No. of Grids Face Velocity Traverse Spacial vs. Temporal Variation fpm 35 fpm Traverse Grid - 30 Readings per Location Analog Velocity - fpm Digital 131 fpm Average = 102 fpm Max = 145 fpm Min = 35 fpm Copyright

12 Flow Monitors and VAV Controls Hood Monitors (Flow Measuring Device) Flow Velocity Pressure Flow Control Types Through the Wall Velocity Sash Position Occupancy Manual Monitors are required on all fume hoods TTW Velocity Sensor and Hood Monitor VAV Modes Two State Full VAV VAV Hybrid VAV Fume Hood Flow Control Sash Open Qex = Vf x Af Sash Closed Qex = Minimum? Flow Reduction = Energy Reduction Flow Terminal Questions? 1. Average Face Sash Open? 2. Minimum Sash Closed? 60 fpm fpm 3. Containment 4. Sash Management Copyright

13 Minimum Flow for VAV Fume Hoods Containment Dilution Removal 1990s - EPA 50 cfm / ft of Wh Duct Conc. (Cd) NFPA cfm / sq. ft. ws Defers to ANSI Z ANSI Z9.5 (must be appropriate) - Internal ACH (150 ACH to 375 ACH) ACH ~ 10 cfm / sq. ft. ws Internal Conc. (Ci) ACH ~ 25 cfm / sq. ft. ws Caution: Minimum Flow is Hood & System Dependent VAV Flow Response and Stability Good Control & Containment DAQ Poor Control & Containment Copyright

14 Average Face Velocity (fpm) Safe. Dependable and Energy Efficient Laboratories April 2014 Controls & Building Automation System (BAS) Fume Hood Face Velocity Tests 140 Syngenta Fume Hood Average Face Velocity Low 39% High 34% Average Face Velocity (fpm) Min fpm = Avg - 10% Max fpm = Avg + 10% 0 Fume Hood ID Copyright

15 Typical Accuracy of VAV Airflow Controls Percent Error - % 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% -10% -20% -30% -40% -50% -60% -70% -80% -90% -100% LET - VAV Terminals - Measured vs BAS Reported - % Error VAV Terminal ID Quality Data - Accuracy and Precision Not Accurate and Not Precise VAV Controls Can degrade Precise but not Accurate 30-50% within 5 years EPA RTP Flow Sensors (Pre LVOP) = 20% to 65% Error Flow Sensors (Post LVOP) = 5% Error Accurate and Precise Copyright

16 VAV Retrofit & Component Upgrades Lab Exhaust to Exhaust Plenum VAV Controller Pressure Transducer Damper Duct Inlet Damper Actuator Flow Grid Flow Connections Grid Lab Flow Damper Actuator Damper Shaft Pressure Transducer Airflow Visualization - Smoke Test Generate Visible Smoke Smoke Tubes, Sticks, Candles Dry Ice Nontoxic Fog Generator Evaluate Air Flow Patterns Qualitatively Evaluate Performance Copyright

17 Airflow Visualization Ratings Fail Visible Escape Poor Reverse Flow at Sash Opening Fair Reverse flow inside Hood within 6 inches. Good No Reverse Flow PWGSC Airflow Visualization Test Standardized Smoke Challenge Controlled Release at Several Locations Mimics Tracer Gas Test Copyright

18 Tracer Gas Containment Test Sulfur Hexafluoride or NO 2 released at 4 LPM with ASHRAE ejector Measure Concentrations in breathing zone of mannequin Test at Center, Left and Right Positions Control Level 4 AM <0.05 ppm 4 AI <0.05 ppm 4 AU < 0.1 ppm Demand for Laboratory Ventilation Operating Mode Min and Max Flow Temperature Control Room Pressure Dilution (ACH) Air Change Effectiveness Qs - Supply Qe - Exhaust Room Pressure Qt = Qe Qs Qt = Constant + - Copyright

19 Typical ACH Guidelines Agency ASHRAE Lab Guides UBC 1997 IBC 2003 IMC 2003 U.S. EPA AIA NFPA NRC Prudent Practices OSHA 29 CFR Part ACGIH 24 th Edition, 2001 Ventilation Rate 4-12 ACH 1 cfm/ft2 1 cfm /ft2 1 cfm/ft2 4 ACH Unoccupied Lab - 8 ACH Occupied Lab 4-12 ACH 4 ACH Unoccupied Lab - 8 ACH Occupied Lab 4-12 ACH Recommends 4-12 ACH Ventilation depends on the generation rate and toxicity of the contaminant and not the size of the room. ANSI/AIHA Z9.5 Prescriptive ACH is not appropriate. Rate shall be established by the owner! Emissions in Labs Requiring Dilution Escape from Lab Hoods Improper Bench Top Procedures Unventilated Equipment Fugitive Emissions Chemical Bottles & Containers Gas Cylinders Accidental Spills Typical Generation Rates <0.1 lpm to 10 lpm Catastrophic Failure of a Gas Cylinder 1400 lpm Copyright

20 Lab Airflow Specifications Control Bands Parameters and Weighting Adapted for Unique Research Labs Specify ACH & Risks of Recirculating Lab Air Evaluate Lab Construction, Pressurization, Need for Monitoring Total Score Control Band ACH Recirculation of Lab Air Lab Isolation & Pressurization < 4 Allowable Neutral Filtered or DCV < w.g Investigate < w.g No >31 5 > 10 No < w.g. Critical w/ Monitor = > w.g. Critical w/anteroom (airlocks) & Monitor Airflow Rates for Labs (ACH?) Survey Laboratories & Evaluate Hazards Sources Exposure Control Devices Supply Diffusers Airflow Effectiveness Determine Generation Emission Scenarios Apply Control Band Matrix Determine Minimum ACH Determine Room Volume Specify Minimum Airflow Copyright

21 System Operating Specifications Max and Min Flows AHUs and Ex. Fans Manifolds Redundancy Emergency Power System Static Pressure Duct Transport Velocity Exhaust Stack Discharge Control Capabilities VAV Diversity VAV Sensitivity Energy Savings Require Reducing Total Building Flow System Flow Controls Outside Air Bypass Inlet Variable Speed Drives Copyright

22 Flow Modulation & VAV Sensitivity Low Flow (Sash Closed) = 1,400 cfm High Flow (Sashes Open) = 7,000 cfm Range of Modulation = 5,600 cfm VAV Sensitivity =? Gex Low = 0 cfm Sash High = 500 cfm Sash Open = 1000 cfm Sash Closed = 200 cfm System Operating Mode Tests (SOMT) SOMT Data Collection Operating Modes o o Sashes Closed - Unoccupied Sashes Open Occupied Measure Total Flow and SP BAS Trend AHUs & Ex. Fans Record Terminal Boxes o o Flow Set Point BAS Flow o Damper % Copyright

23 System Operating Mode Tests (SOMT) Operating Mode Sashes Closed - Unoccupied 100% Sashes Open - Occupied Flow BAS Flow BAS Damper Terminal Serves Sash Ht. Damper% Sash Ht. Setpoint Flow Setpoint Flow % EVAV1 LFH EVAV2 Gex1 n/a n/a EVAV3 LFH EVAV4 LFH BAS Trend 797 of Combined 765 Flow for 28 AHUs 11&12,13&14,15&16,19&20 EVAV5 Gex3 n/a n/a 100 (Week September September 9, 2012) EVAV6 LFH EVAV7 Gex2 n/a n/a EVAV8 LFH EVAV9 LFH EVAV10 LFH Aggregate Terminal Flow n/a n/a Total BAS Flow Measured Flow VFD% OABD% BAS System SP Meas. System SP Flow - cfm /1/12 12:00:00 AM PDT 9/1/12 6:00:00 AM PDT 9/1/12 12:00:00 PM PDT 9/1/12 5:30:00 PM PDT 9/1/12 11:00:00 PM PDT 9/2/12 5:00:00 AM PDT 9/2/12 11:00:00 AM PDT 9/2/12 5:00:00 PM PDT 9/2/12 11:00:00 PM PDT 9/3/12 5:00:00 AM PDT 9/3/12 11:00:00 AM PDT 9/3/12 5:00:00 PM PDT 9/3/12 11:00:00 PM PDT 9/4/12 5:30:00 AM PDT 9/4/12 11:30:00 AM PDT 9/4/12 5:00:00 PM PDT 9/4/12 11:00:00 PM PDT 9/5/12 5:00:00 AM PDT 9/5/12 11:00:00 AM PDT 9/5/12 4:30:00 PM PDT 9/5/12 10:30:00 PM PDT 9/6/12 4:30:00 AM PDT 9/6/12 10:30:00 AM PDT 9/6/12 4:00:00 PM PDT 9/6/12 10:00:00 PM PDT 9/7/12 4:00:00 AM PDT 9/7/12 10:00:00 AM PDT 9/7/12 3:30:00 PM PDT 9/7/12 9:30:00 PM PDT 9/8/12 3:30:00 AM PDT 9/8/12 9:30:00 AM PDT 9/8/12 3:30:00 PM PDT 9/8/12 9:30:00 PM PDT 9/9/12 3:30:00 AM PDT 9/9/12 9:30:00 AM PDT 9/9/12 3:00:00 PM PDT 9/9/12 9:00:00 PM PDT Average Minimum Flow - cfm Maximum Flow - cfm Aggregate AHU Flow - cfm Building Pressurization Copyright

24 Optimize Stack Discharge and Dispersion Re-entrainment Stack Height > 10 ft. Stack Velocity? (3000 fpm) Optimum Design Lab Safety and Energy Programs Lab Safety and Energy Assessment Quick, Low Cost, Low Risk Audit Evaluate Safety & Code Compliance Determine Performance Improvement Measures (PIMs) Determine Energy Conservation Measures (ECMs) Determine Benefits, Potential Energy Reduction, Cost and Payback Lab Ventilation Optimization Project (LVOP TM ) Engineer & Implement PIMs and ECMs TAB Commission Systems Lab Ventilation Management Plan (LVMP) Maintain Safe & Efficient Operation Ensure Compliance Conduct Routine Test and Maintenance Protect Return on Energy Investment Plan Assess Optimize Sustain Copyright

25 Assess and Profile Laboratory Buildings Qualify Facility and Buildings Select & Prioritize Best Projects First Key Metrics & Weighting Factors Size & Space Allocation Energy Use & Operating Costs State of the Systems Energy Reduction Potential Lab Safety and Energy Profile Building Classification Assessment of Energy Reduction Estimated Project Costs & Payback Attribute Lab Building Profile Category State of the Systems Energy Reduction Potential Project LOE & Complexity Return on Investment (Payback) Class A Class B Class C Class D Class E Lab Safety and Energy Optimization Project Phase 1 Project Engineering Determine Operating Specifications Control Band Hoods & Labs Design Upgrades & System Modifications Develop TAB & Cx Plans Phase 2 Upgrade/Renovation Project Implement Selected PIMs & ECMs Verify Performance and Energy Savings Copyright

26 Lab Safety & Energy Optimization Projects RELSA = Rapid Energy & Lab Safety Assessment SOW = Scope of Work PIM = Performance Improvement Measure ECM = Energy Conservation Measures TA = Technical Assistance Vendor TAB = Test, Adjust and Balance Cx = Commissioning Tests LVMP = Lab Ventilation Management Program Assessment Profile and Optimization Tasks Attribute Building Profile Profile State of the Systems Building Operating Cost Energy Reduction Potential Energy Project Complexity (LOE) A B C D E (New) ROI - Project Payback < 3 < 5 < 10 > 10 N/A Planning RELSA & TA Study X X X X Safety & Energy Optimization Project Sustainability Program Minor Engineering X X Major Engineering X X Component Repair Maintenance X X X X Retrofits & Component Upgrades X X X Component Replacement X X New Equipment Installation Project Phase & Task TAB X X X X CX X X X X LVMP X X X X X Training X X X X X Routine T&M Services X X X X X X Copyright

27 Demand Based Optimization - LVOP Success Building Baseline Airflow cfm Annual Operating Cost $ Final Airflow cfm Flow Reduction cfm % Flow Reduction Annual Cost Savings $4.50/cfm-yr GHG Reduction tons/yr Gov 1 (5 bldgs) 773,000 3,478, , ,000 33% 1,147,500 15,300 Gov 2 ( 1 bldg) 66, ,000 37,000 29,000 44% 130, Gov 3 (1 bldg) 71, ,500 56,000 15,000 21% 67, Gov 4 (2 bldgs) 144, , ,000 43,000 30% 193, Gov 5 (1 bldg) 51, ,500 35,000 16,000 31% 72, Gov 6 (1 bldg) 47, ,500 33,000 14,000 30% 63, Biotek 1 (1 bldg) 11,000 49,500 7,000 4,000 36% 18, Pharma 1 ( 4 bldgs) 628,000 2,826, , ,000 26% 711,000 9,720 Pharma 2 (1 bldg) 168, , ,000 48,000 28% 216, University 1 (1 bldg) 394,000 1,773, ,000 62,000 16% 279, University 2 (1 bldg) 180, , ,000 45,000 25% 202, Summary 2,533,000 $11,398,500 1,844, ,808 29% $3,100,500 41,700 Safe Sustainable Energy Use Ensure ROI Campus Wide Aggregate Energy Reduction Billion BTUs Energy Baseline Energy Target Reduction 14.7% $900,975 4th Q rd Q nd Q st Q nd Q st Q th Q rd Q 2005 Copyright

28 Laboratory Ventilation Management Program (LVMP) System Management and Sustainability Plan Organization and Responsibilities Lines of Communication (Reporting) SOP s for Surveys, Testing and Maintenance Metrics, Monitoring & BAS Utilization Ventilation Standards Management of Change Personnel Training Required By ANSI Z Responsible Person Ventilation Maintenance and Test Schedule Copyright

29 Training of Personnel Lab Personnel Facility Maintenance Building Operators Lab Safety and Energy Efficiency Plan Assess Optimize Safe Energy Efficient Dependable Sustainable Sustain Copyright

30 END QUESTIONS? Thomas C. Smith 231-C East Johnson St. Cary, NC Copyright