Statesville, NC Results of AM ASHRAE 11 Laboratory Fume Hood Performance Evaluations Venturi Hood January, 217 Prepared By: Exposure Control Technologies Inc. 231-C East Johnson Street Cary, NC 27513 Phone: (919) 319-429 Fax: (919) 319-4291 www.exposurecontroltechnologies.com
CONTENTS EXECUTIVE SUMMARY... 1 RECOMMENDATIONS... 1 METHODOLOGY... 3 HOOD PERFORMANCE TESTS: STATIC SASH... 3 Face Velocity Test... 3 Cross Draft Tests... 4 Airflow Visualization Tests... 4 Tracer Gas Tests... 5 Periphery Scan Test... 6 Sash Movement Effect (SME) Test... 6 RECOMMENDED PERFORMANCE CRITERIA... 7 TEST RESULTS... 8 Table I: Laboratory Fume Hood Performance Test Results... 8 STANDARD OPERATING PROCEDURES FOR HOOD USE... 9 APPENDIX A... CERTIFICATES OF CALIBRATION APPENDIX B... HOOD INFORMATION AND PERFORMANCE TEST DATA SHEETS
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 1 EXECUTIVE SUMMARY This report provides results of As Manufactured (AM) performance tests conducted on one constant air volume (CAV) six-foot Venturi model laboratory fume hood within the Kewaunee Scientific fume hood testing laboratory located in Statesville, North Carolina. Exposure Control Technologies, Inc. performed the tests on January 23-24, 217. Testing was performed in accordance with guidelines provided in the ANSI/ASHRAE 11-216 "Method of Testing Performance of Laboratory Fume Hoods." The criteria for performance were adopted from recommendations by the ACGIH, the National Research Council, SEFA, ANSI, and relevant industry standards on laboratory ventilation. The hood was tested As Manufactured (AM) at the 28 vertical full open sash height, at 4 fpm face velocity and with the hood both empty and box-loaded. RECOMMENDATIONS The ASHRAE 11 tests were conducted under a variety of scenarios, as follows: ASHRAE 11 test, hood clear, 4 fpm test. ASHRAE 11 test, hood box-loaded per NIH standard, 4 fpm test. Results of testing revealed that the fume hood met acceptance criteria as described herein, with average tracer gas containment results below the industry AM standard of.5 ppm. Testing and evaluation were performed by: Randy Blew Senior Laboratory Services Project Manager
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 3 METHODOLOGY Hood Performance Tests: Static Sash All performance tests were conducted with the sash at the vertical full open height of 28 inches. Measurement of Face Velocity Measurement of Cross Drafts Visualization of Airflow Patterns Measurement of Tracer Gas Containment Periphery Scan Test Sash Movement Effect (SME) Tests Face Velocity Test The face velocity tests were performed by dividing the opening of the hood into equal area grids of approximately 1 square foot and measuring the velocity at the center of each grid. Air velocities were recorded at one-second intervals for 1 seconds at each grid location. The mean of the grid velocities were averaged for the opening to determine the overall average face velocity. The mean grid velocities can be used to evaluate spatial and temporal variation of velocities across the opening. Refer to Figure 1. Figure 1: Diagram of hood opening showing face velocity traverse locations
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 4 Cross Draft Tests Potentially interfering cross drafts were measured in front of the hood opening with a pair of calibrated thermo-anemometers. Measurements were made with the probes positioned vertically and horizontally parallel to the side edge of the hood approximately 5 feet above the floor and approximately 18 inches from the left, center, and right edge of the hood enclosure. Cross draft velocities were recorded at one-second intervals for 3 seconds and averaged. Velocity of air flowing into the hood due to exhaust flow has negligible effect on cross draft velocities. Refer to Figure 2 for a diagram of cross draft test locations. Figure 2: Plan and elevation diagram showing location of cross draft measurements. Airflow Visualization Tests Smoke was generated in the hood and around the periphery of the opening using a Rosco Fog Generator. Smoke patterns were observed to identify escape and reverse flow zones. A low volume of smoke was generated along the periphery of the opening and inside the hood at approximately 6 inches inside the plane of the sash (low-flow). A high volume of smoke was also discharged inside the hood and the clearance time and smoke patterns were noted (highflow). Observations were rated subjectively based on the table provided in the following section "Recommended Performance Criteria."
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 5 Tracer Gas Tests The tracer gas containment tests were conducted to evaluate and quantify the potential for contaminant escape in the presence of a mannequin. A mannequin was used to simulate the presence of a hood user. The mannequin was positioned at the left, center and right of the hood opening with the nose approximately 3 inches in front of the plane of the sash. A tracer gas, Sulfur Hexafluoride, was released from an ASHRAE 11 ejector at 4 liters per minute (lpm) 6 inches behind the plane of the sash directly in front of the mannequin. Breathing zone concentrations were measured every second for 5 minutes in each test location using a calibrated USON Qualichek 2 Trace Gas Leak Detector. The leak detector was calibrated against a calibration gas standard immediately prior to the start of tests and validated after tests were conducted. Average, minimum and maximum breathing zone concentrations were determined from the data. The leak detector has an upper limit of detection of 2 parts per million (ppm). Refer to Figure 3 for a diagram of the test configuration. Figure 3: Configuration of mannequin at hood opening during tracer gas tests.
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 6 Periphery Scan Test The Periphery Scan Test was conducted by configuring the sash to the maximum vertical operational opening and positioning the SF6 ejector at the center of the hood opening as described above for the Tracer Gas Test. The periphery of the hood s opening was then scanned with the USON Qualichek 2 Trace Gas Leak Detector s probe to determine areas of possible containment loss. While standing away from the face of the hood, the probe was held 1 inch away from the edge of the hood opening and moved slowly around the opening at a rate of approximately 3 inches per second for 12 seconds to identify any potential leakage points. Sash Movement Effect (SME) Test The Sash Movement Effect Test consisted of recording tracer gas escape data while raising and lowering the sash at a rate of approximately 1.5 feet per second. The sash was closed for approximately 3 seconds and opened for approximately 6 seconds throughout the fiveminute test. The values for tracer gas were recorded at a rate of 1 sample per second using a laptop computer and data acquisition system. Refer to Figure 4 for a diagram of the test configuration. Figure 4: Diagram of typical setup of Sash Movement Effect Test
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 7 RECOMMENDED PERFORMANCE CRITERIA The following criteria are assembled from industry consensus standards and are provided as an aid in the evaluation of performance data. The criteria are based on SEFA, ANSI Z9.5, ACGIH, and relevant ventilation standards. The criteria apply to the following tests: Smoke Visibility Test Hood must provide complete containment of the smoke generated within the hood. Containment was determined visually and in the absence of the mannequin. Results are reported as a qualitative judgment of airflow distribution according to the following rating guide: RATING DESCRIPTION FAIL Smoke was visually observed escaping from the hood Reverse flow of smoke is evident near opening LOW PASS Lazy flow into hood along openings (Poor) Slow capture and clearance Observed potential for escape PASS (Fair) HIGH PASS (Good) Some Reverse flow in hood not necessarily at opening Limited turbulent vortex flow inside hood Smoke is captured and clears readily No visible escape Good capture and quick clearance Limited vortex flow inside hood No reverse flow regions No visible escape Face Velocity Test Hood should have a minimum average face velocity of 5-6 fpm at the low volume setting. The face velocity readings should not vary more than 2% of the mean between grid locations. Cross Draft Test Cross draft velocities should not exceed 5 fpm near the hood opening. Ideally, cross draft velocities should be less than 3 fpm. High cross draft velocities are particularly detrimental to hood performance when sashes are opened beyond the design operational opening. Tracer Gas Challenge Test Hood should provide containment of tracer gas below an average of ppm measured for a period of 5 minutes in the breathing zone of a stationary mannequin positioned directly in front of the ejector location. Periphery Scan Test Hood should provide containment of tracer gas below an average of ppm and peak concentrations should be less than 1 ppm measured for a period of 2 minutes while scan is conducted. SME Test The hood should provide containment of tracer gas below an average of ppm measured in the breathing zone of a stationary mannequin positioned directly in front of the ejector location.
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 8 TEST RESULTS Table I: Laboratory Fume Hood Performance Test Results Average Face Velocity (fpm) Exhaust Flow 1 (cfm) Tracer Gas Avg. 2; 3 (ppm) Left Center Right Per. Scan Cross Draft Max Avg. (fpm) Smoke Visualization Test SME Horiz. Vert. Low High Comments Performance Rating 41 52 <.1 <.1 <.1.1 <.1 <.1 <.1 <.1 <.1 <.1 16 2 Pass (Fair) Pass (Fair) Pass (Fair) Pass (Fair) ASHRAE 11 test, hood clear, 4 fpm test. ASHRAE 11 test, hood box-loaded per NIH standard, 4 fpm test. Pass Pass Table I Notes: 1. Calculated Exhaust Flow (cfm) = measured average face velocity (fpm) x face opening area (sq.ft). 2. 5-minute avg. tracer gas concentration in mannequin s breathing zone. 3. 2 minute avg. tracer gas concentration for periphery scan test (refer to Appendix B Test Data Sheets for max concentration readings).
Kewaunee Scientific: Venturi AM Hood Performance Testing January 217 9 STANDARD OPERATING PROCEDURES FOR HOOD USE The following is a list of guidelines for working in the fume hood: 1. Minimize the sash opening when possible. 2. Do not adjust baffle positions. 3. Elevate contaminants and equipment 1-2 inches above the work surface within the hood(s). 4. If equipment and material storage are necessary, locate along the sidewalls or well away from the point of contaminant generation. Do not store any equipment that restricts the closing of the sash or blocks the bottom slot of the baffle directly in front of the employee. 5. Keep movements in the hood and in front of the hood to a minimum. 6. Keep movements within the lab to a minimum while working in the hood(s). Traffic past the hood(s) can generate considerable cross drafts. 7. Keep head and upper body outside the plane of the hood(s) opening at all times. 8. Always approach and withdraw from hood(s) slowly. Open and close the sash slowly.
APPENDIX A Certificates of Calibration
APPENDIX B Hood Information and Performance Test Data Sheets
Conditions: Datasheet - Laboratory Hood Performance Test Results Report printed on 2/9/217 Company Name: Building Name: Laboratory: Sash Opening: Opening Dimensions: Main Kewaunee Test Lab Hood: Venturi 6 foot Full open sash Height 28 inches Baffle Opening: Normal Apparatus In Hood: No Clear for tests. Monitor Reading - As Found: n/a Diff. Pressure Occupied: Test Comments: ASHRAE 11 test, 4 fpm test. Smoke Visibility Test Results: Low Volume Rating: Comments: Cross-Draft Test Results: Pass (Fair) Positions: Left Center Right Horiz.: Max: 18 23 23 Avg: 2 14 16 Vertical Max: 25 16 21 Avg: 2 9 7 Perpend.: Max: Avg: Hood Face-Velocity Test Results: Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Date: Cycle Index: Cycle Rating: 1/24/217 Width Major Area Additional Area Total Area 63 inches 12.25 ft^2 ft^2 12.25 ft^2 High Volume Rating: Pass (Fair) Lazy and reverse flow along worksurface. Reverse flow in corners of opening. Reverse flow within six inches of opening. Turbulent vortex in top of hood. Col 1 Col 2 Col 3 Col 4 Col 5 Col 6 Col 7 Col 8 Col 9 Col 1 Col 11 Col 12 42 42 36 42 43 42 36 37 42 38 36 4 4 45 45 4 4 44 Tracer Gas Test Results: Position: Tested: Average: Minimum: Maximum: As Left: n/a Un-Occupied: 1 2 3 4 Left Center Right Collection Method: Collection Method: Collection Method: ppm ppm ppm 3 Pass Avg: Max: Min: Exhaust Flow: 41 45 36 52 DAQ Max Avg DAQ fpm fpm fpm cfm DAQ
Plots of Tracer Gas Containment Report printed on 2/9/217 Hood: Venturi 6 foot Date: 1/24/217 Cycle: 3 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3.9.8.7.6.5.4.3.2.1 3 6 9 12 15 18 21 24 27 3 Left Center Right Average: Maximum: Minimum:
SME Test Report printed on 2/9/217 Hood: Date: Cycle: Venturi 6 foot 1/24/217 3 Sash Opening: Other Test Conditions: Full open sash ASHRAE 11 test, 4 fpm test. # Samples: Sample Duration: # Samples per Second: 1 3 1 2 1.9 15.8.7 Velocity = fpm 1.6.5.4 5.3.2 3 Flow Response Cross Draft Tracer Gas Escape Flow Response Cross Draft Tracer Gas Escape 1.. 3 seconds Average: Maximum: Minimum: 3 17 1 7 Speed of Response Rating: Speed of Response Time: VAV Comment: N/A Stability Rating: Stability Percent Variation: N/A
Conditions: Datasheet - Laboratory Hood Performance Test Results Report printed on 2/9/217 Company Name: Building Name: Laboratory: Sash Opening: Opening Dimensions: Main Kewaunee Test Lab Hood: Venturi 6 foot Full open sash Height 28 inches Baffle Opening: Normal Apparatus In Hood: No Clear for tests. Monitor Reading - As Found: n/a As Left: n/a Diff. Pressure Occupied: Un-Occupied: Test Comments: Periphery scan, ASHRAE 11 4 fpm test. Smoke Visibility Test Results: Low Volume Rating: Positions: Horiz.: Max: Avg: Vertical Max: Avg: Perpend.: Max: Avg: Comments: Cross-Draft Test Results: Hood Face-Velocity Test Results: Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Date: Cycle Index: Cycle Rating: 1/24/217 Width Major Area Additional Area Total Area 63 inches 12.25 ft^2 ft^2 12.25 ft^2 High Volume Rating: Col 1 Col 2 Col 3 Col 4 Col 5 Col 6 Col 7 Col 8 Col 9 Col 1 Col 11 Col 12 Tracer Gas Test Results: Position: Tested: Average: Minimum: Maximum: 1 2 3 4 P-scan.1.5 Collection Method: Collection Method: Collection Method: ppm ppm ppm 4 Pass Avg: Max: Min: Exhaust Flow: DAQ
Plots of Tracer Gas Containment Report printed on 2/9/217 Hood: Venturi 6 foot Date: 1/24/217 Cycle: 4 1.9.8.7.6.5.4.3.2 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12 Average: Maximum: Minimum: P-scan.1.5
Conditions: Datasheet - Laboratory Hood Performance Test Results Report printed on 2/9/217 Company Name: Building Name: Laboratory: Sash Opening: Opening Dimensions: Main Kewaunee Test Lab Hood: Venturi 6 foot Full open sash Height 28 inches Baffle Opening: Normal Apparatus In Hood: Yes Box-loaded per NIH. Monitor Reading - As Found: n/a Diff. Pressure Occupied: Test Comments: Box-loaded ASHRAE 11, 4 fpm test. Smoke Visibility Test Results: Low Volume Rating: Comments: Cross-Draft Test Results: Pass (Fair) Positions: Left Center Right Horiz.: Max: 18 23 23 Avg: 2 14 16 Vertical Max: 25 16 21 Avg: 2 9 7 Perpend.: Max: Avg: Hood Face-Velocity Test Results: Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Date: Cycle Index: Cycle Rating: 1/24/217 Width Major Area Additional Area Total Area 63 inches 12.25 ft^2 ft^2 12.25 ft^2 High Volume Rating: Pass (Fair) Lazy and reverse flow along worksurface. Reverse flow in corners of opening. Reverse flow within six inches of opening. Turbulent vortex in top of hood. Col 1 Col 2 Col 3 Col 4 Col 5 Col 6 Col 7 Col 8 Col 9 Col 1 Col 11 Col 12 42 42 36 42 43 42 36 37 42 38 36 4 4 45 45 4 4 44 Tracer Gas Test Results: Position: Tested: Average: Minimum: Maximum: As Left: n/a Un-Occupied: 1 2 3 4 Left Center Right.4 Collection Method: Collection Method: Collection Method: ppm ppm ppm 5 Pass Avg: Max: Min: Exhaust Flow: 41 45 36 52 DAQ Max Avg DAQ fpm fpm fpm cfm DAQ
Plots of Tracer Gas Containment Report printed on 2/9/217 Hood: Venturi 6 foot Date: 1/24/217 Cycle: 5 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3 1.9.8.7.6.5.4.3.2 3 6 9 12 15 18 21 24 27 3.9.8.7.6.5.4.3.2.1 3 6 9 12 15 18 21 24 27 3 Left Center Right Average: Maximum:.4 Minimum:
SME Test Report printed on 2/9/217 Hood: Date: Cycle: Venturi 6 foot 1/24/217 5 Sash Opening: Other Test Conditions: Full open sash Box-loaded ASHRAE 11, 4 fpm test. # Samples: Sample Duration: # Samples per Second: 1 3 1 2 1.9 15.8.7 Velocity = fpm 1.6.5.4 5.3.2 3 Flow Response Cross Draft Tracer Gas Escape Flow Response Cross Draft Tracer Gas Escape 1.. 3 seconds Average: Maximum: Minimum: 1 Speed of Response Rating: Speed of Response Time: VAV Comment: N/A Stability Rating: Stability Percent Variation: N/A
Conditions: Datasheet - Laboratory Hood Performance Test Results Report printed on 2/9/217 Company Name: Building Name: Laboratory: Sash Opening: Opening Dimensions: Main Kewaunee Test Lab Hood: Venturi 6 foot Full open sash Height 28 inches Baffle Opening: Normal Apparatus In Hood: Yes Box-loaded per NIH. Monitor Reading - As Found: n/a As Left: n/a Diff. Pressure Occupied: Un-Occupied: Test Comments: Periphery scan, Box-loaded ASHRAE 11, 4 fpm test. Smoke Visibility Test Results: Low Volume Rating: Positions: Horiz.: Max: Avg: Vertical Max: Avg: Perpend.: Max: Avg: Comments: Cross-Draft Test Results: Hood Face-Velocity Test Results: Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Date: Cycle Index: Cycle Rating: 1/24/217 Width Major Area Additional Area Total Area 63 inches 12.25 ft^2 ft^2 12.25 ft^2 High Volume Rating: Col 1 Col 2 Col 3 Col 4 Col 5 Col 6 Col 7 Col 8 Col 9 Col 1 Col 11 Col 12 Tracer Gas Test Results: Position: Tested: Average: Minimum: Maximum: 1 2 3 4 Center.11 Collection Method: Collection Method: Collection Method: ppm ppm ppm 6 Pass Avg: Max: Min: Exhaust Flow: DAQ
Plots of Tracer Gas Containment Report printed on 2/9/217 Hood: Venturi 6 foot Date: 1/24/217 Cycle: 6 1.9.8.7.6.5.4.3.2 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12.9.8.7.6.5.4.3.2.1 12 24 36 48 6 72 84 96 18 12 Average: Maximum: Minimum: Center.11