Biological containment : Microbiological safety cabinets.

The dangers of airborne infection in the laboratory; Schlieren photography clearly illustrates the problems with heat convection around typical laboratory equipment such as a bunsen burner and the microenvironment around the the body. Safety cabinets of different designs are discussed dependent on the requirement for laboratory safety. National standards have been produced about the use and limitations of safety cabinets; the effectiveness of the three different classes of cabinet is explained via animations. The Schlieren method of photography aptly illustrates poorly designed safety cabinets in the past as a result of research. Modern safety cabinets are shown in use with Schlieren photography. A discussion of how the cabinets are tested for appropriate safety follows.