Evolution of microbiological safety cabinets.

Microbiological safety cabinets have had a chequered history, often being confused with chemical fume cupboards and cabinets intended to protect cultures from contamination rather than workers from infection. They have suffered from incorrect and inapt names. Much work has been required to determine the levels of air flow necessary to contain infectious particles and to prevent the exhaust of those particles to the environment, and this is considered in historical sequence. Warnings are given about the shortcomings of portable and home-made cabinets. This review traces the evolution of these cabinets, from the time of Robert Koch to the development of good national standards.