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, such as primary cultures, stocks and diagnostic specimens 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. The Biological Cabinets divide to 3 classes: Class I biological safety cabinet, Class II biological safety cabinets, Class III biological safety cabinet.