Biosafety Cabinet

A biosafety cabinet (BSC) — also called a microbiological safety cabinet (MSC) — is an enclosed, ventilated laboratory workspace. A BSC protects the operator and the environment from pathogenic materials and volatile chemicals.

There are three types of biosafety cabinets; the biosafety level specifies which cabinet should be used:

BSC Class	Protection provided	Biosafety level	Principle
Class I	Protects the operator only.	1-3	These are open-fronted, and the air is drawn in entirely via the front opening.
Class II	Protects both work and operator.	1-3	Also open-fronted, with the air drawn in via the front, but it is drawn through a HEPA filter before being blown over the work.
Class III	Offers maximum protection to both the user and the work.	3,4	These are fully enclosed, with glove ports, and the air is drawn into the cabinet via a HEPA filter. The operator is therefore segregated from the work by a solid barrier.
Class I/III	Protects both work and operator.	1-3	Capable of running in either Class I or Class III mode.