Microbiological laboratory
The elements of design and construction of a laboratory (secondary barriers) help to protect both the laboratory personnel and the people, animals and plants outside against any infectious agents released by accident.
In BSL-1 and BSL-2 laboratories the risk of infection is basically by direct contact or exposures to unnoticed contacts. Therefore, secondary barriers prevent public access to the work area and decontamination and washing facilities are available.
When there is risk of infection from exposure to a bioaerosol a higher level of containment must be implemented, with multiple secondary barriers to prevent infectious agents from spreading into the environment. This includes specialised ventilation systems to control air flow (from outside to inside), HEPA filtration of the extracted air, controlled-access areas, airlocks or SAS changing-rooms, waste-treatment systems, free-standing buildings or modules, etc.