These are bio-enclosures that are commonly used for microbiological analysis. These cabinets are suitable for Biosafety levels I to IV where samples being handled range from non-pathogenic to those with lethal effects.
The biosafety cabinet with the most basic design. Filtration system works by trapping all airborne particles and contaminants from the air that enters the unit through a HEPA (High Efficiency Particulate Air) Filter. Finally, clean and decontaminated air is exhausted from the cabinet.
Class I cabinets only provide operator and environment protection but does not protect the samples handled inside the cabinet from being in contact from airborne contaminants. This allows the possibility of cross-contamination that may affect experimental reliability and consistency.