The biosafety cabinet must have adequate lighting which does not blind or hinder the vision of the biosafety cabinet user. The lighting apparatus must be installed in an area which can be decontaminated. A drill spillage trough should be provided below the work surface to retain spillage. The spillage trough will catch spilled liquids, which can potentially contaminate the biosafety cabinet interior. The trough must be easily cleanable and capable of withstanding chemical disinfectants.
Flexible connections are less likely to result in the release of gas during an earthquake.
Firm connections may be pulled right out of the wall and subsequently result in a gas leak. B type cabinets into one vertical duct is not permitted. It is extremely difficult to balance the air in the rooms where hard ducted biosafety cabinets are installed. The system must be turned off if servicing or repairs are needed. The annual certification procedure is also more difficult because of the potential off-gassing or backflow of paraformaldehyde into other biosafety cabinets on the system.