Work opening, biological safety cabinets

Class U The Class U (Types A, Bl, B2, and biological safety cabinets provide personnel, environmental, and product protection. Airflow is drawn around the operator, through the hood opening and into the front grill of the cabinet, which provides personnel protection, in addition, the downward flow of HEPA-filtered air provides product protection by minimizing the chance of cross-contamination along the work surface of the cabinet. Because cabinet air has passed through the exhaust HEPA filter, it... 

All manipulations involving infectious materials are to be conducted in biological safety cabinets orotherphysical containment devices within the containment module.No work in open vessels is to be conducted on the open bench. 

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