A biological safety cabinet (BSC) is a primary engineering control used to protect personnel against biohazardous or infectious agents and to help maintain quality control of the material being worked with as it filters both the inflow and exhaust air. It is sometimes referred to as a laminar flow or tissue culture hood.
These filtered cabinets are primarily designed to protect against exposure to particulates or aerosols. A portion of the air in most BSCs is recirculated back into the lab through its exhaust HEPA filter. This purifies the air of potentially infectious aerosols, animal dander, or both but does not reduce exposure to chemicals.
All procedures should be performed in a manner that reduces the generation of aerosolized material and prevents spills. Operations such as centrifugation, vortexing, sonication, and opening containers of infectious materials whose internal pressure may be different from the ambient pressure are known aerosol-generating procedures. These procedures should be conducted inside the BSC or additional measures must be available to mitigate the safety concern.