389D000 Rev B
12
Working in the Cabinet
WARNING
Never work inside the cabinet when an alarm indicator light is on
This section contains some suggested basic work practices that should be observed when using a Biological
Safety Cabinet. It is not intended to be a comprehensive list for all applications. A good reference source is The
Biosafety In Microbiological and Biomedical Laboratories (BMBL) 5
th
edition published by the U.S.
Department of Health & Human Services as HHS Publication No. (CDC) 21-1112.
advisory document for safe work practices.
The Operator’s hands and arms should be washed thoroughly with germicidal soap both before and after
working in the cabinet. It is recommended that long-sleeved gowns or lab coats with tight-fitting cuffs
and sterile gloves are worn. This minimizes the shedding of skin, or related contaminants, into the work
area and protects hands, arms and clothing from contamination.
Avoid using floor-type pipette discard canisters. It is important that used pipettes be discarded into a
tray or other suitable container inside the cabinet. This reduces the need to move in and out of the work
area unnecessarily.
Because of the restricted access, pipetting within the cabinet will require the use of pipetting aids.
All work should be performed using the recessed area of the solid work surface. Work should be
performed using slow movements. The number of movements should be limited as much as possible.
All of the materials required should be placed in the cabinet prior to starting a procedure to reduce the
need for the operator to move arms in and out of the cabinet through the air barrier.
Room airflow can significantly affect cabinet operation. Opening and closing doors in the laboratory can
cause air disturbances which might interfere with cabinet airflow. This kind of activity should be kept to
a minimum while the cabinet is in use. Personnel should avoid walking by the front of the cabinet while
it is in use. The location of facility air diffusers and personal fans can have an adverse effect on cabinet
safety.
Use good aseptic technique
The operating position of the sash is either an 8” [203mm], 10” [254mm], or 12” [305mm] access
opening as determined by the certification of the cabinet. This defined opening provides optimum
operating conditions for the cabinet. Because operators will not all be the same height, it is suggested
that the operator use a height adjustable chair or similar device when working in the cabinet.
When a procedure has been completed, all equipment that has been in contact with the research agent
should be enclosed, and the entire work surface decontaminated. Trays of discarded pipettes, glassware,
etc. should be covered. The cabinet should then be allowed to run for a minimum of three minutes, with
no activity, so that the airborne contaminants will be purged from the work area. Once this has been
done remove all equipment from the cabinet.
WARNING
Never use the cabinet to store supplies or laboratory equipment.
When all materials have been removed, all interior surfaces should be decontaminated. Check the work
area carefully for spilled or splashed nutrient that might support bacterial growth.
It is recommended that the cabinet be left running continuously to ensure containment and cleanliness.
The sash alarm is not activated when the window is in the fully closed position.
