Exhaust approximately 30% of total air handled and recirculate 70%
Minimum inflow air velocity is 100 fpm (0.51 m/s) through the front opening
Audiovisual alarm required when connected to a exterior system
May exhaust HEPA filtered air back into the room or through a canopy
Have biologically contaminated ducts and plenums under negative pressure or surrounded by negative pressure ducts and plenums
Type A2 cabinets may be used for work with minute quantities of volatile toxic chemicals and tracer amounts of radionuclides if they are exhausted through properly functioning exhaust canopies.
