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Deal with low levels of volatile toxic chemicals and trace quantities of radionuclides might be performed towards the back of the work surface area, where the air is discharged directly to the outside environment. In this type of BSC, the supply blower draws room air into the top of the cabinet, through a HEPA filter, and after that downwards over the work surface area (Figure 11-5).

Type B2 BSCs are hard-ducted. Work with unpredictable harmful chemicals and radionuclides may be performed in the BSC considering that the air is never recirculated within the BSC or within the containment zone. Turnaround of air flow from the face of a BSC, likewise called a, can take place in Class II type B2 BSCs, for instance upon failure of the heating and cooling system, power, or the exhaust fan serving the BSC.


7). When puff- This Site occur in, the lab is considered infected and full space may be required. Consideration must likewise be provided to the quantity of air needed to run this type of cabinet as it may cause additional adjustments to balance the airflow in the containment zone. Table 11-1: Summary Table of Key Characteristics of Class II Biological Security Cabinets (BSCs) Type A1 Type A2 Type B1 Type B2 Minimum typical inflow velocity through front opening 0.