§ 627.52 - Class III biological safety cabinet.

(a) Description. These cabinets (figure H-III in appendix F to this part) are totally enclosed, ventilated cabinets of gas-tight construction. Operations are conducted through attached rubber gloves. The supply of air is drawn into the cabinet through HEPA filters. The exhaust air is treated by double HEPA filtration, or by HEPA filtration followed by incineration, and is not allowed to recirculate within the room.

(b) Uses. These cabinets provide the ultimate protection for personnel. They are suitable for low, moderate, and high-risk etiologic agents.

(c) Prohibitions. More than minute amounts of flammables must not be used in these cabinets.

(d) Certifications and requirements. (1) These cabinets will have a manometer or magnehelic gauge that indicates the negative pressure that is maintained inside the cabinet. The pressure inside the cabinet should be a minimum of 0.5 inches water gauge negative to the surrounding room.

(2) These cabinets will be pressure tested by the soap bubble or halogen leak test as prescribed in NSF Standard No. 49, appendix B1 (latest revision, June 1987), and certified, when the HEPA filter units are serviced.