Tom Schwaller, SEFA Chairman Vice President, Labconco Corporation. Dominique Laloux General Manager, Erlab China

Transcription

1 Tom Schwaller, SEFA Chairman Vice President, Labconco Corporation Dominique Laloux General Manager, Erlab China You can download a copy of this presentation from the link on the homepage at

2 SEFA Recommended Practices For Laboratory Fume Hoods

3 FORWARD SEFA s Recommended Practices are designed to promote a better understanding between designers, architects, manufacturers, purchasers, and end users.

4 The Fume Hood Committee 29 people from 26 companies (In 2010) Collective wisdom to promote improved quality, safety, and timely completion of laboratory facilities with customer requirements.

5 Laboratory Fume Hood Defined A laboratory Fume Hood is a safety device specifically designed to carry undesirable effluents (generated within the hood during a laboratory procedure) away from laboratory personnel and out of the building, when connected to a properly designed laboratory ventilation system.

6 Laboratory Fume Hood Defined A Laboratory Fume Hood shall be made primarily of flame resistant materials including top, three sides and a single face opening. Face opening is equipped with a sash and sometimes an additional protective shield. Face opening will have a profiled entry and usually an airfoil designed to sweep and reduce reverse airflows on the surface. A Laboratory Fume Hood will be equipped with a baffle and, in most cases, a bypass system designed to control airflow patterns within the hood and manage the even distribution of air at the opening. The bypass system may be partially blocked to accommodate Variable Air Volume (VAV) Systems. A Laboratory Fume Hood will be set on a bench, a pedestal or on the laboratory floor.

7 Laboratory Fume Hood As Manufactured Components Baffles Collar Bypass Sash Types Services Fire Suppression Hood Types Auxiliary Air ASHRAE 110 Testing Energy Efficient Hoods

8 Redesigned Bypass Aerodynamic Sash Frame New Baffle Configuration Energy Efficient Low Profile Sill Laboratory Fume Hood

9 Laboratory Fume Hoods As Installed Location in the Lab Safety Considerations Hood Evaluation Room Conditions Sash Operation Face Velocity ASHRAE Testing Trouble Shooting Maintenance

10 Laboratory Fume Hoods As Used Safe Work Practices Plan for Conducting Experiments Wear Appropriate Personal Protection ASHRAE Testing Annually Utilize Proper Work Practices Proper Location of Equipment and Apparatus Responsibilities for Ensuring Proper Hood Performance

11 Types of Ventilated Devices Demonstration Hoods California Hoods Ventilated Enclosures Local Exhaust Ventilation Canopy Slot Snorkel Laminar Flow Biological Safety Cabinets Glove Box Ductless Enclosures SEFA-9

12 Bio-Safety Cabinets Class I Cabinets - A ventilated cabinet that provides personnel and environmental protection. It is characterized by an unrecirculated inward flow of air away from the operator through a limited fixed access opening. Exhaust air must be HEPA filtered if recirculated back into the laboratory. It may or may not be vented via a remote ventilation system. This cabinet does not offer product protection. Class II Cabinets - A ventilated cabinet that provides personnel, product and environmental protection. It is characterized by a limited fixed inward airflow access opening that provides personnel protection, a vertical downward HEPA filtered work zone that provides product protection and HEPA filtered exhaust providing environmental protection. They are divided into types by NSF and identified in Standard 49.

13 Class III Cabinets (Glove Box) - Provides absolute personnel protection, environmental protection and may provide product protection. It is characterized by a totally enclosed, gas-tight, negative pressure, HEPA filtered, ventilated workspace accessed through attached rubber gloves and purged interchange chambers. Exhaust air is treated by double HEPA filtration and/or incineration. Reference Organizations NSF International (NSF Standard 49) American Glove Box Society

14 Regulatory and Industry Consensus Standards American Conference of Governmental and Industrial Hygienists ANSI/AIHA Z ANSI/ASHRAE ASHRAE Handbook Applications 1999 NFPA 45, 2000 OSHA Prudent Practices Handbook of Laboratory Safety

15 Conclusion SEFA standards are developed by a diverse international group of laboratory furniture manufacturers SEFA 1 explains Laboratory Fume Hoods in terms of As Manufactured, As Installed, and As Used conditions SEFA-1 directs interested parties to relevant organizations and government agencies that produce documents concerning laboratory ventilation, laboratory fume hoods and laboratory safety.

16 SEFA Recommended Practices For Ductless Enclosures

17 Ductless Hood Filtration Categories DH I Non-toxic chemicals, nuisance DH II Designed to filter manufacturer approved toxic contaminants up to filter break through only. Not designed to provide secondary containment beyond primary filter break through.

18 DH III Capable of meeting all DH II requirements and equipped with a filtration device designed to filter manufacturer approved toxic contaminants beyond primary filter break through by providing secondary back-up protection. DH III should be designed to provide a period of time to continue and end an ongoing experiment with its secondary back-up filter system. Prior to approving usage, a qualified specialist or department within the manufacturer or supplier of the Ductless Hood should review all applications and determine for each the compatibility or incompatibility of the ductless hood by using form SEFA 9-A.

19 SEFA-9A Form SEFA 9-A standardized form designed to answer all pertinent questions regarding the intended usage of a ductless hood and ultimately guide the end-user in the correct use of their ductless hood. Form SEFA 9-A should be posted in the space provided on the ductless hood at all times. Response form SEFA 9-A should include: The application approval reference number; The approved application and corresponding list of approved toxic substances; The approval date; The approved filter type; The estimated filter life; The filtration system date of first use and estimated date of replacement; Information regarding the automatic filter saturation detection system; The model and serial number of the ductless hood; A warning dedicating the ductless hood to the approved application only; A warning for Category II ductless hoods indicating the need to stop the procedure immediately following filter saturation detection;

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22 Approved Applications The manufacturer or supplier of the Ductless Hood should approve all applications prior to usage. The formal response form SEFA 9-A given to the Ductless Hood operator is a necessary document as it represents an agreed upon understanding of correct dedicated use between the supplier and the operator. Ductless Hood manufacturers/suppliers are required to integrate within their organization the means necessary to scientifically approve each potential application. Responsibility of the end user to advise the manufacturer of the Ductless Hood and gain the approval of all applications in writing prior to usage.

23 Change of Use Operators shall obtain prior written re-approval from the manufacturer every time an application varies in any way from the initial approved usage. There is no difference between a change of application and a new usage qualification. SEFA spells SAFE

24 SEFA 9 Benchmark Testing As Manufactured DH I - No testing required. DH II and DH III - Calibration of testing equipment refer to ASHRAE for calibration guidelines. Hood setup and face velocity measurements refer to SEFA section 4.3 and/or ANSI/ASHRAE Face Velocity Measurements or most current version.

25 Flow Visualization Discharge smoke from a smoke stick along the walls and work surface of the hood six inches back from the front of the unit. At no time shall smoke escape out the hood, except through the filtered exhaust. If smoke does escape out the front of the hood the hood fails the test.

26 Containment Testing Refer to ASHRAE or most current version for specific details. No leakage of tracer gas shall be greater than an average of 0.05 ppm in any position. Refer to ASHRAE for instrumentation, ejector construction and method details.

27 Filter Efficiency and Adsorption Capacity Tests NIOSH Limits Chemical Family TLV Evaporation Rate HCL 5 ppm 100 ppm Diethyl Amine 10 ppm 50 ppm Isopropyl 400 ppm 500 ppm Toluene 100 ppm 150 ppm

28 Suitable ways of Evaporation are: Free surface evaporation without heat Heating the chemical in a container on a hot plate Adding the chemical into a metal or ceramic cup heated by a hot plate using a peristaltic or other high precision positive displacement pump set to the required mass flow rate. Determine the evaporation rate of the chemical by weighing the container(s) before and after the evaporation, with an appropriate precision balance or scale and noting weight change per unit time. Monitor the concentration of the test chemical in the room, in the hood, before the filter and in the exhaust stream past the filter(s) under test by using a gas chromatograph, mass spectrometer, FTIR analyzer or PID detector.

29 The instrumentation used shall have a minimum detection level of 1% of the TLV or less. If hydrochloric acid is tested an ion chromatograph or FTIR is recommended. Exhaust air from the hood must be sampled at 15 minute time intervals. For each data point, record or calculate the mass of chemical evaporated as well as chemical concentration levels in the sampled air streams. The test output shall be a table or graph of the mass of the test chemical evaporated plotted as the x-axis vs. the concentration in ppm of the chemical concentration found in the hood exhaust on the y-axis.

30 Ductless Hoods As Installed A test protocol must be provided by the manufacturer for DH-II and DH-III hoods to verify that the unit is functioning to manufacturer s specifications. Validate manufacturer s claims for face velocity, base containment, filter sealing and instantaneous filtration, as well as verifying the display of face velocity and emissions monitoring systems.

31 If surrogate chemical challenge is specified, the recommended chemical must be of low toxicity and readily available for use, i.e. isopropyl alcohol or similar. Face velocity monitors may be verified simultaneously with actual face velocity test above. Test procedure should contain provisions for verifying alarm functions.1

32 Safe Work Practices Operators should use Ductless Hoods in accordance with their organization s safety guidelines and have a clear understanding of the limitations and capabilities of their Ductless Hood prior to usage. In general, Ductless Hoods are not recommended for usage with unknown chemicals or reactions. Ductless Hood usage should be limited to manufacturer approved applications only.

33 Markings Ductless Hoods should be clearly identified with the words DUCTLESS HOOD prominently displayed in large letters on the front of the product in order to differentiate them from conventional ducted Fume Hoods. DH ratings, identified in this work practice as DH I, II and III, should also be prominently displayed in large letters on the front of the product, along with reference to SEFA 9.

34 DH I Ductless Hood Label should note their inability to provide protection for anything other than nuisance odorous compounds. DH II Ductless Hood Label should contain a message requiring the immediate suspension of usage at the time of saturation detection. An area on the Ductless Hood should be provided in plain view for the placement of form SEFA 9-A. If removed the form shall let the following words appear: NOT RECOMMENDED FOR USE WITHOUT CURRENT APPLICATION APPROVAL FORM SEFA 9-A IN PLACE. A sticker stating the recommended sash/door position should be placed on the enclosure.

35 QUESTIONS DISCUSSION

36 SEFA Desk Reference SEFA 1, SEFA 9 and all of SEFA s other Recommended Practices are contained in the SEFA Desk Reference. The 5 th Edition Desk Reference will be released in early April SEFA World Headquarters 65 Hilton Avenue Garden City, NY USA You can download a copy of this presentation from the link on the homepage