Safety cabinet inhalation protection

When an individual breathes in polluted air, any substance may enter the respiratory tract causing direct harm to the respiratory system and indirect harm due to uptake via ingestion. Especially sensitising substances may require attention. As airways and the lung caimot be closed off, only ventilation (exhaustion) and filtration of inhaled air remain as protective measures, such as working in safety cabinets and wearing masks with air filters (respirators). 

The air within a safety cabinet comes from the HEPA filter in the top of the cabinet (see Fig. 28. If). The flow is led into exit grills at the back and the front of the work bench. A second airflow is drawn from the working room into the front grill where the elbows of the operator are. This flow prevents air or aerosols from the working area escaping the cabinet and protects the operator from inhaling aerosols. 

BSL 3 Biosafety Level 3 is for work with indigenous or exotic microorganisms, which may cause serious or potentially lethal disease if inhaled. Safety equipment Class I or II biosafety cabinets or other physical containment devices protective laboratory clothing, gloves, respiratory protection as needed. Microorganisms include Mycobacterium tuberculosis, Bacillus anthracis, and Coxiella burnetii. 

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