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THE ORCBS > Biological Safety > Programs & Guidelines > Biosafety Manual >
Biological safety cabinets (BSCs) are designed to protect the operator, the laboratory environment and work materials from exposure to infectious aerosols and splashes that may be generated when manipulating materials containing infectious agents. Aerosol particles are created by any activity that imparts energy into a liquid, such as shaking, pouring, stirring or dropping liquid onto a surface or into another liquid. Other laboratory activities, such as streaking agar plates, inoculating cell culture flasks with a pipette, using a multichannel pipette to dispense liquid suspensions of infectious agent into microculture plates, homogenizing and vortexing infectious materials, and centrifugation of infectious liquids, or working with animals, can generate infectious aerosols. Aerosol particles of less than 5 µm in diameter and small droplets of 5-100 µm in diameter are not visible to the naked eye. These particles may be inhaled or may cross contaminate work surface materials. BSCs, when properly used, have been shown to be highly effective in reducing laboratory-acquired infections and cross-contaminations of cultures due to aerosol exposures. BSCs also protect the environment. BSCs are designed to provide personnel, environmental and product protection when appropriate practices and procedures are followed. Three kinds of biological safety cabinets, designated as Class I, II and III are available. Biological safety cabinets use high efficiency particulate air (HEPA) filters in their exhaust and/or supply systems. The HEPA filter traps 99.97% of particles of 0.3 µm in diameter and 99.99% of particles of greater or smaller size. Biological safety cabinets must not be confused with other laminar flow devices or "clean benches." Horizontal flow cabinets direct air towards the operator and should never be used for handling infectious or toxic materials. For information on biological safety cabinets, beyond what is in the manual, please refer to the CDC/NIH publication: Primary Containment for Bi ohazards Selection, Installation and Use of Biological Safety Cabinets. |
Safety Equipment: Biological Safety Cabinets (BSCs)
