BSC Class II, Type A2: These biosafety cabinets may be exhausted to the room or connected to a facility exhaust system via a “canopy” connection (NSF recommends a canopy connection for cabinets exhausted to the outdoors).


Class II Protection From Particulates From Vapors and Gases
Type A1, Type A2 Personnel, work area (products) and environment
  • If exhausted to room: none; not for use with vapors and gases
  • If exhausted to facility exhaust system, protects personnel
  • If exhausted to a treated facility exhaust system protects personnel, the work area and the environment