How to choose Biological Safety cabinets
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According to European Standard EN 12469:2000, types of Biological Safety Cabinets are divided into three classes: Biological Safety Cabinet Class I is a ventilated cabinet that provides personnel and environmental protection. It is characterized by an unrecirculated inward flow of air away from the operator through a limited fixed access opening. The operation principle is based on the forced removal of contamination from the working area by unidirectional rising air stream, refinement of removing air by filtration system and its exhaust into the external ventilation system. Biological Safety Cabinet Class II is a ventilated cabinet that provides personnel, product and environmental protection. The cabinet operation is based on forced air recirculation in confined space through superfine fiber filters. Moving through HEPA filters air comes to the working area by unidirectional falling stream. Due to artificially made air evacuation, there is air curtain preventing cross-contamination “working agent – operator”. Biological Safety Cabinet Class III is a cabinet which provides absolute personnel, environment and product protection. It is characterized by a totally enclosed, HEPA filtered, ventilated workspace accessed through attached gloves and purged interchange chambers. The operation is based on forced air supply into the working cabinet and then the removal of contaminated air through the two-level refining system.
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