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Lab Ventilation Safety & Energy Efficiency
Helping Facilities Ensure Safe, Energy Efficient & Sustainable Laboratory Buildings Fran Boucher National Grid 781-907-1571
[email protected]
Thomas C. Smith
Exposure Control Technologies, Inc. 919-319-4290
[email protected]
Safe, Dependable and Energy Efficient Laboratories
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Agenda & Topics
Introduction
Laboratory Safety & Risks Laboratory Hoods & Ventilation Systems Lab Ventilation - Energy Use & Costs 2012 ANSI/AIHA Z9.5 Standard Requirements & Recommendations Lab Ventilation Safety & Energy Survey – A National Grid Program
Recommended for Owners, EH&S Personnel, Building Managers, Facility Engineers, and Energy Engineers associated with Laboratory Ventilation Systems in Research Laboratory Buildings. Safe, Dependable and Energy Efficient Laboratories
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Goal: High Performance Laboratories Chemistry Labs Radiological Labs
Biology Labs (high containment)
Nanotechnology Labs
Cleanrooms
•
Animal Vivariums
Safe • Compliant with Codes & Standards
•
Productive (Flexible)
•
Energy Efficient
•
Sustainable Safe, Dependable and Energy Efficient Laboratories
Laboratory Hazards Risk of Adverse Health Effects Inhalation Hazards
Airborne Materials
Toxicity
Generation Rate & Concentration
Duration of Exposure
Physical Hazards
Contact - Dermal Exposure
Fire & Explosion
Dose = Concentration x Duration Safe, Dependable and Energy Efficient Laboratories
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Laboratory Hoods & Ventilation Systems
Proper Performance = Protection Proper Performance = Compliance Operation ≈ 60% Utility Costs
STACK
Cost = $ 3 to $ 9 per cfm-yr
FILTER
FAN ROOF DUCTS
AIR SUPPLY
THINK SAFETY
LAB
OFFICE
Safe, Dependable and Energy Efficient Laboratories
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Laboratories & Fume Hoods Laboratories are rated one of the highest energy users by building type
Fume hoods are the primary means of protecting lab personnel Fume hood performance can be affected by numerous factors Average Annual Energy Cost of 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 / ft2
Hospital
$ 3 / ft2
Laboratory
$ 7 / ft2
Specialty Labs & Cleanrooms
≥ $ 15 / ft2
Lights
10% HVAC
60%
Safe, Dependable and Energy Efficient Laboratories
30%
Plug/Misc.
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Evaluating Fume Hood Safety ANSI/ASHRAE 110 “Method of Testing Performance of Laboratory Fume Hoods” Mannequin
Determine Operating Conditions
• • • •
Tracer Gas Ejector
Hood and Lab Inspection
Computer & DAQ
Face Velocity Measurements Cross Draft Velocity Tests VAV Response and Stability
Determine Performance (Containment )
• •
Tracer Gas Detector
Flow Visualization Smoke Tests
Face Velocity Probe
Cross Draft Probe
Tracer Gas Containment Tests
Methods to Evaluate Containment Performance and Ensure Safe Hoods Safe, Dependable and Energy Efficient Laboratories
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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
• Work practices - 25% Safe, Dependable and Energy Efficient Laboratories
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Causes of Inadequate Performance Improper: • • • •
Design Operation Maintenance Use
Safe, Dependable and Energy Efficient Laboratories
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ANSI/AIHA –Z9.5 - 2012 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 Safe, Dependable and Energy Efficient Laboratories
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Specifications for Safe & Energy Efficient Labs
Laboratory Hood Operation –
Monitors & VAV Controls –
Construction Specs & Performance Criteria Types, Accuracy and Operating Modes
Laboratory Design & Operation –
ACH & Air Change Effectiveness
–
Diffuser Type and Location
–
Temperature & Humidity Control
Ventilation Design & Operation –
Duct Velocity & Static Pressure
–
Stack Discharge
–
Recirculation & Energy Recovery
Commissioning and Routine Tests –
ASHRAE/ANSI 110 “Method of Testing Performance of Laboratory Fume Hoods”
–
Lab Environment Tests
–
System Operating Mode Tests Safe, Dependable and Energy Efficient Laboratories
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Types of Laboratory Fume Hoods
Bench-Top – Traditional Bypass – Low Velocity / High Performance – VAV – Restricted Bypass
Distillation
Floor Mounted (Walk-in)
Safe, Dependable and Energy Efficient Laboratories
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Fume Hood Operation and Specifications Supply Flow
Exhaust Flow
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
Airflow Controls •
CAV
•
VAV
Safe, Dependable and Energy Efficient Laboratories
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High Performance Fume Hoods • Full Open Sash • Face Velocity: 60 - 70 fpm • Equivalent or Better Containment than Traditional Fume Hoods @ 100 fpm • Safe & Proven Technology • Numerous Hood Manufacturers – Lab Crafters – Fisher Hamilton – Kewaunee Scientific
– Labconco – Air Master – Others
• EPA Tested & Approved Safe, Dependable and Energy Efficient Laboratories
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Retrofit-Upgrade Traditional Fume Hoods Upgrade Critical Components
• • •
Airfoil Sill
Renew/Refurbish Inefficient Hoods Improve Safety & Containment
Sash Handle
Reduce Flow and Energy Use
Baffle
Typical Reduction = 20% to 40%
Safe, Dependable and Energy Efficient Laboratories
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Upgrade & Retrofit Fume Hoods Before
After
Safe & Sustainable Technology Safe, Dependable and Energy Efficient Laboratories
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Flow Monitors and VAV Controls •
Hood Monitors (Flow Measuring Device) – Flow – Velocity – Pressure
•
Monitors are required on all fume hoods
Flow Control Types – Through the Wall Velocity – Sash Position
– Occupancy – Manual
VAV Modes
– Two State – Full VAV – VAV Hybrid
Safe, Dependable and Energy Efficient Laboratories
TTW Velocity Sensor and Hood Monitor
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VAV Flow Response & Stability
Good Containment
Poor Containment & Intermittent Escape Measure Slot Velocity or
Exhaust Flow
Safe, Dependable and Energy Efficient Laboratories
VAV Flow Response and Stability Sash Open
Sash Closed Good Control & Containment VAV Terminal
Poor Control & Containment
Safe, Dependable and Energy Efficient Laboratories
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Minimum Flow for VAV Fume Hoods •
•
Containment
•
Dilution
1990s - EPA – 50 cfm / ft of Wh
Removal
Duct Conc. (Cd)
2004 - NFPA 45 25 cfm / sq. ft. ws 2010 - Defers to ANSI Z9.5
2012 - ANSI Z9.5 (must be appropriate) Internal ACH (150 ACH to 375 ACH) 150 ACH ~ 10 cfm / sq. ft. ws Internal Conc. (Ci)
375 ACH ~ 25 cfm / sq. ft. ws Bench-Top Fume Hood Size - ft
Internal Volume (Vh) ft3
4
29.6
180
180
70
6
48.2
300
300
120
8
66.9
410
410
160
Min Flow cfm ANSI Flow cfm ANSI Flow cfm (NFPA) (375 ACH) (150 ACH)
Caution: ECT finds 150 ACH too low Safe, Dependable and Energy Efficient Laboratories
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Laboratory Airflow Specifications
Qe - Exhaust
Operating Mode Min and Max Flow Temperature Control
Dilution – ACH Air Change Effectiveness Room Pressure
Transfer Volume Qt = Qe – Qs Qt = Constant Room Pressure
+
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Safe, Dependable and Energy Efficient Laboratories
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Typical ACH Guidelines Agency
Ventilation Rate
OSHA 29 CFR Part 1910.1450
4-12 ACH
ASHRAE Lab Guides
4-12 ACH
UBC – 1997
1 cfm/ft2
IBC – 2003
1 cfm /ft2
IMC – 2003
1 cfm/ft2
U.S. EPA
4 ACH Unoccupied Lab - 8 ACH Occupied Lab
AIA
4-12 ACH
NFPA-45-2004
4 ACH Unoccupied Lab - 8 ACH Occupied Lab
NRC Prudent Practices
4-12 ACH
ACGIH 24th Edition, 2001
Ventilation depends on the generation rate and toxicity of the contaminant and not the size of the room. Prescriptive ACH is not appropriate.
ANSI/AIHA Z9.5
Rate shall be established by the owner. Dilution is seldom effective – source capture preferred
Safe, Dependable and Energy Efficient Laboratories
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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 15%
Developed/ Implemented LVMP
* = Projects in Progress Average Annual Energy Reduction ≥15% Safe, Dependable and Energy Efficient Laboratories
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END
QUESTIONS? Fran Boucher
Thomas C. Smith
National Grid
Exposure Control Technologies, Inc.
781-907-1571
919-319-4290
[email protected]
[email protected]
Safe, Dependable and Energy Efficient Laboratories
