Classes of biological safety cabinets
Biological safety cabinets (BSCs) are used to protect personnel, products and the environment from exposure to biohazards and cross contamination during routine procedures. When choosing a biological safety cabinet for your work space, EH&S can help you select the class of cabinet that will provide the best protection.
There are three classes of BSCs: Class I, II and III. While all three classes afford personnel and environmental protection, only Class II and III cabinets provide product protection.
- Class I BSCs are suitable for work involving low to moderate-risk agents. Since incoming air is not filtered, Class I BSCs should not be used with research materials (e.g., cell lines) that must be handled under sterile conditions. Class I cabinets are used to enclose equipment (e.g., centrifuges, harvesting equipment or small fermenters) or procedures with potential to generate aerosols (e.g., cage dumping, tissue homogenization or culture aeration). Because outgoing air is filtered, research personnel are protected while using a Class I BSC.
- Class II BSCs provide a partial barrier for the safe manipulation of low, moderate and high-risk microorganisms. Class II cabinets, which are the most frequently used in research and clinical laboratories, are divided into four types (Types A1, A2, B1 and B2).
- The Class III BSC is a totally enclosed, gas-tight ventilated cabinet, and provides the highest level of personnel, environmental and product protection. Operations within a Class III BSC are conducted through attached rubber gloves.