President�s Report by rsnRgbG5

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									   LABORATORY
   VENTILATION
      FOR TULANE UNIVERSITY
     LABORATORY & DESIGNATED
       FACILITIES EMPLOYEES
                        May 2012



Tulane University - Office of Environmental Health & Safety (OEHS)
                  OBJECTIVES
• To learn about the different types of ventilation
  available in laboratories so that laboratory
  workers can become familiar with the types of
  equipment and the limitations associated with
  each type
• To learn tips and safe work practices on how to
  safely operate a fume hood and a biological safety
  cabinet
• To become familiar with the role of OEHS in the
  purchase and certification of fume hoods and
  biological safety cabinets
      Tulane University - Office of Environmental Health & Safety (OEHS)
    GOALS OF VENTILATION
• Ventilation may be designed to protect the worker
  from potentially hazardous inhalation hazards:
  - toxic or volatile chemicals
  - particles or dusts
  - vapors or aerosols
  - infectious microorganisms
  - other inhalation hazards
• Ventilation may be designed to protect the product
  from contamination
• Ventilation may be designed with filters to clean the
  air being exhausted from the unit, thereby
  protecting the environment
          Tulane University - Office of Environmental Health & Safety (OEHS)
CHEMICAL FUME HOODS
                               • Designed to protect the
                                 worker from toxic or
                                 hazardous chemicals
                               • 100% of air exhausted to
                                 outside
                               • No recirculation of air
                               • Baffles in back should
                                 adjust for work with
                                 chemicals of different
                                 volatilities and vapor
                                 densities

  Tulane University - Office of Environmental Health & Safety (OEHS)
CHEMICAL FUME HOODS
                             • All chemical fume hoods at
                               Tulane must have an alarm
                               or airflow indicator device on
                               them to show that they are
                               operating properly
                             • Most chemical fume hoods
                               should have a face velocity in
                               the range of 80-100 fpm


  Tulane University - Office of Environmental Health & Safety (OEHS)
CHEMICAL FUME HOODS
                             • Do not assume that your
                               fume hood is operating
                               properly. Check the alarm
                               indicator. At the very least,
                               use a piece of tissue paper
                               and make sure it is drawn
                               inward. IF NOT
                               OPERATING PROPERLY,
                               DISCONTINUE WORK
                               WITH HAZARDOUS OR
                               TOXIC CHEMICALS!
  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Keep the sash as low as
                                 possible
                               • Work at least 6 inches
                                 inside hood
                               • Keep work surface clear of
                                 unnecessary items
                               • Keep baffles clear of
                                 obstructions – elevate large
                                 equipment off work surface

  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Avoid rapid movement into
                                 and in front of hood
                               • Pedestrian traffic in front
                                 of hood creates turbulence
                                 and can pull vapors out of
                                 hood and into operator’s
                                 breathing zone



  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Keep the amount of material in
                                 a hood to a minimum – excessive
                                 clutter increases turbulence and
                                 reduces hood efficiency
                               • An airfoil helps to minimize
                                 undesirable turbulence when air
                                 entering the hood impacts the
                                 front edge of the floor of the
                                 hood – be sure airfoil is installed
                                 and side panels are in place


  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Secure loose lightweight
                                 objects such as paper towels
                               • Run water in hood drains
                                 often to reduce odors that
                                 may develop in p-trap
                               • Ensure adequate
                                 illumination in hood
                               • Be aware that opening and
                                 closing lab doors can affect
                                 hood performance

  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Keep the sash clean and
                                 unobstructed
                               • Place cords and hoses
                                 under the airfoil so sash can
                                 be kept closed
                               • Practice good housekeeping
                               • Clean chemical residues
                                 and spills from interior
                                 hood surfaces

  Tulane University - Office of Environmental Health & Safety (OEHS)
FUME HOOD SAFETY TIPS
                               • Do not place absorbent
                                 paper under heating
                                 appliances
                               • Do not place incompatible
                                 chemicals together
                               • Remember – the emptier
                                 the hood, the better air
                                 currents can flow through
                                 it! Do not use hood as
                                 storage cabinet.

  Tulane University - Office of Environmental Health & Safety (OEHS)
RADIATION FUME HOODS
                  • Designed for worker protection for
                    work with radioactive materials
                  • 100% of air exhausted to outside
                  • May contain HEPA filters (esp. for
                    work with Iodine isotopes)
                  • Usually stainless steel construction
                  • Usually reinforced for heavy lead
                    shielding


  Tulane University - Office of Environmental Health & Safety (OEHS)
RADIATION FUME HOODS
                  • Most radiation fume hoods should
                    have a face velocity of about 125
                    fpm
                  • Same safety tips as for chemical
                    fume hoods apply




  Tulane University - Office of Environmental Health & Safety (OEHS)
   PERCHLORIC ACID FUME
          HOODS
• Work with perchloric acid can cause the
  formation of perchlorate salts which can
  buildup in the hood and ductwork and
  become explosive




     Tulane University - Office of Environmental Health & Safety (OEHS)
   PERCHLORIC ACID FUME
          HOODS
• Designed for worker protection for work
  with perchloric acid
• 100% of air exhausted to outside
• Special washdown features to prevent
  perchlorate buildup in hood and
  ductwork
• Not to be used for flammables or other
  chemicals reactive with perchlorates

     Tulane University - Office of Environmental Health & Safety (OEHS)
                  ROLE OF OEHS
• OEHS approves fume hood purchases after
  checking with Facilities Services or building
  engineers and the researcher to make sure the
  equipment will meet the researcher’s needs
• OEHS checks fume hood performance usually on
  an annual basis and reports problems to Facilities
  Services
• Contact OEHS or Facilities Services if you suspect
  there is a problem with the performance of your
  fume hood – DO NOT USE TOXIC OR
  VOLATILE CHEMICALS if you suspect a
  potential problem

        Tulane University - Office of Environmental Health & Safety (OEHS)
SLOT VENTILATION
                         • Designed for worker
                           protection from volatile
                           materials
                         • 100% Exhausted to outside
                         • Draws fumes towards back of
                           work space away from
                           worker’s breathing zone
                         • Often used in pathology or
                           histology laboratories


Tulane University - Office of Environmental Health & Safety (OEHS)
CANOPY VENTILATION
                           • May be 100% exhausted to
                             outside, but not
                             recommended for chemical
                             use
                           • Draws fumes past worker’s
                             breathing zone
                           • Best used for heat removal
                             such as in a kitchen


 Tulane University - Office of Environmental Health & Safety (OEHS)
              HEPA FILTERS
• HEPA stands for high efficiency
  particulate air filter
• A HEPA filter filters out particles – not
  fumes and vapors
• HEPA filters are used in biological safety
  cabinets



     Tulane University - Office of Environmental Health & Safety (OEHS)
CLASS I BIOLOGICAL SAFETY
          CABINET
• Designed for worker protection
• 100% Exhausted through HEPA filter
  directly back into the room
• Supply air not filtered, so product in
  cabinet is subject to contamination by
  organisms present in the air supply
• May be equipped with arm-length rubber
  gloves

     Tulane University - Office of Environmental Health & Safety (OEHS)
Laminar Flow Clean Bench
                         • A laminar flow clean bench is
                           designed specifically to protect
                           the product from contamination
                         • Not designed to protect the
                           operator




 Tulane University - Office of Environmental Health & Safety (OEHS)
Laminar Flow Clean Bench
                         • Supply air passes through
                           HEPA filter over work surface,
                           then is exhausted to the room
                         • Exhaust air actually blows into
                           operator’s face
                         • Never handle toxic or infectious
                           materials in a Laminar Flow
                           Clean Bench


 Tulane University - Office of Environmental Health & Safety (OEHS)
          Biological Safety Cabinet (BSC)
               Selection & Approval
• Units are selected based upon the hazards imposed by the
  infectious agent(s) utilized in the lab, the biosafety level, and
  the lab procedure(s) that will be conducted
• A PI’s requisition to buy a unit(s) is forwarded from
  Purchasing to the OEHS for review and approval
   – PI provides info to OEHS on activities that will be
     conducted
   – OEHS ensures PI’s equipment needs and lab are adequate
     for the activities that will be performed
• Written approval is forwarded by OEHS to Purchasing upon
  review and determination that unit will provide protection
  needed for the activities that will be conducted.

            Tulane University - Office of Environmental Health & Safety (OEHS)
CLASS II TYPE A BIOLOGICAL SAFETY
             CABINETS
                     • Protects the worker, the product, and
                       the environment
                     • Most commonly used BSC, suitable for
                       procedures with clinical specimens or
                       cell cultures
                     • Some air is recirculated within cabinet
                       through a HEPA filter, some air is
                       exhausted back into lab through another
                       HEPA filter
                     • Two (2) Subtypes
                           – A1 – “freestanding” unit
                           – A2 – unit with a thimble connection
                     • Do not use toxic or flammable materials
     Tulane University - Office of Environmental Health & Safety (OEHS)
CLASS II TYPE B BIOLOGICAL SAFETY
             CABINETS
•   Provides protection for worker, product, and environment
•   Provides containment of infectious aerosols
•   Units are hard-ducted
•   Two (2) subtypes
    – B1 – Recirculates some air within the cabinet
    – B2 – Does not recirculate air in the cabinet
• Exhaust requirements
    –   Sufficient building air needed to operate
    –   Install an alarm
    –   Interlock units fan with the building exhaust system
    –   Fan required on the roof
• Do not use toxic or flammable materials

             Tulane University - Office of Environmental Health & Safety (OEHS)
CLASS III BIOLOGICAL SAFETY
           CABINET
              • Gas tight construction with rubber
                gloves
              • Supply air is drawn through a
                HEPA filter and exhaust air is
                filtered through 2 HEPA filters
                installed in series before discharge to
                the outside
              • Provides highest level of worker,
                product, and environmental
                protection

  Tulane University - Office of Environmental Health & Safety (OEHS)
             BSC CERTIFICATION
• Performed on new unit before usage, after filter changes,
  after a unit is moved from one location to another, and
  when deemed necessary if a problem arises
• Typically conducted annually by an outside contractor
  through OEHS
• Performed by individual(s) trained to perform
  certifications and troubleshoot unit
• Conducted in accordance with the National Sanitation
  Foundation (NSF) International Standard No. 49 for Class
  II (Laminar Flow) Biohazard Cabinetry
• Includes all or some of the following tests: HEPA Filter
  Leak, Inflow & Downflow Velocity Profile, Airflow Smoke
  Patterns, Electrical, Noise, Lighting, and Vibration

         Tulane University - Office of Environmental Health & Safety (OEHS)
          BSC Use & Safe Work Practices
• Operate the unit at least three to five minutes before beginning
  work to allow the cabinet to "purge"
• Wipe the unit work surface, (not including the supply filter
  diffuser), the interior surface of the window, and the surfaces
  of all materials and containers placed into the cabinet with an
  appropriate disinfecting solution
• Ensure proper placement of one’s arms, absorbent towels, and
  materials inside the unit to prevent disruption to the airflow
• Ensure active work inside the unit from a clean to a
  contaminated area
• Decontaminate materials that will be removed from the BSC at
  the conclusion of work activities
• DO NOT PLACE ITEMS ON TOP OF THE UNIT


             Tulane University - Office of Environmental Health & Safety (OEHS)
            BSC Use & Safe Work Practices
• Clean small spills immediately with an appropriate
  decontaminating solution and place items used to clean
  in a biohazard bag
• Consult OEHS for spills large enough to result in
  liquids flowing through the front or rear grilles that
  may require more extensive decontamination
• Gas decontamination, performed only by OEHS or
  specially trained personnel, may be performed or
  required:
   – After a particular project involving use of a highly
     infectious agent
   – Prior to maintenance activities
   – Prior to certification or performance tests
   – Before HEPA filter replacement
   – Before a unit is moved from one location to another
   – After a major spill of a biohazardous material
             Tulane University - Office of Environmental Health & Safety (OEHS)
          BSC Use & Safe Work Practices
• OEHS recommends that the use of natural gas or
  any other flammable material in a BSC be
  prohibited except for cabinets that are equipped
  with explosion-proof roof exhaust fans. Use of
  these materials in a BSC can present a potential
  fire or explosion hazard as air is recirculated in the
  unit, can cause turbulence and disrupt airflow
  patterns, and the heat produced by a Bunsen
  burner can damage the HEPA filter.
• Electric burners and micro-incinerators may be
  workable alternatives to using gas. These devices,
  however, may still create heat and turbulent
  airflow in the cabinet. To minimize these effects,
  the electric burner or micro-incinerator should
  only be used in the rear of the workspace.
          Tulane University - Office of Environmental Health & Safety (OEHS)
              BSC Safe Work Practices for
                Maintenance Activities
• Call OEHS for guidance before commencement of work
• Ensure unit is decontaminated prior to maintenance
  activities requiring work inside of a contaminated plenum
• Do not allow maintenance personnel to:
   – perform work (i.e., change light) inside the unit without
     performing a surface wipe
   – perform work with the UV Light “ON”
   – cut holes in the unit
   – change HEPA filters in the unit
   – sit items on top of the unit
   – puncture the filters inside of the unit
          Tulane University - Office of Environmental Health & Safety (OEHS)
            DUCTLESS HOODS
• The use of ductless fume hoods is
  discouraged for most applications (Problems:
  No indicator to tell when filter needs to be
  changed, multiple chemicals can interfere
  with filtration, small spills can overwhelm
  filtration system, etc.)
• If used, filter must be changed frequently in
  accordance with manufacturer’s
  recommendations

       Tulane University - Office of Environmental Health & Safety (OEHS)
                         SUMMARY
• Chemical and radiation fume hoods exhaust
  100% to the outside and can safely be used
  for work with toxic or volatile chemicals
• HEPA filters, usually found in biological
  safety cabinets, filter out particles, not fumes
  and vapors
• For best performance when using a fume
  hood or BSC, please follow suggested safety
  tips and safe work practices
        Tulane University - Office of Environmental Health & Safety (OEHS)
                          SUMMARY
• BSCs are selected based upon the hazards imposed
  by the infectious agent(s) utilized in the lab, the
  biosafety level, and the lab procedure(s) that will be
  conducted
• Certification of BSCs and fume hoods is typically
  done on an annual basis and when new equipment
  is installed or filters changed
• Call OEHS for guidance before maintenance
  activities commence on a BSC – decontamination
  may be needed

         Tulane University - Office of Environmental Health & Safety (OEHS)
   Tulane University
Office of Environmental Health & Safety (OEHS)
           Pam Fatland (504) 988-2800
          Kim Chapital (504) 988-2870
              http://tulane.edu/oehs
   pfatlan@tulane.edu or kchapit@tulane.edu


 If unable to proceed to quiz, type the link below into your browser   Proceed to Quiz
    https://pandora.tcs.tulane.edu/ehs/enterssn.cfm?testnum=100

								
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