The Clean bench method for detecting leaks

 According to the requirements of the Clean Bench industry-standard JG/T292-2010, the Clean Bench is mainly detected by scanning. Specifically, it refers to the poor sealing of the filter and the installation frame due to the leakage holes on the filter material and the frame of the high-efficiency (or ultra-high-efficiency) air filter. Detection of aerosol leakage caused by incorrect installation of filters.

Clean bench
 
The detection method is to evaluate whether it is leakage according to the ratio of downstream particle concentration to upstream particle concentration (hundred points). When atmospheric dust is used, the number of downstream particles can be evaluated. The concentration should be ≤3 particles /L, and the leakage penetration rate should be ≤0.01% by the DOP method. The workbench used for biological cleaning purposes should also be tested for sedimentation bacteria concentration ≤0.5cfu/(dish.0.5h).
 
When detecting, use atmospheric dust or multi-dispersed aerosol as the source of pollution. When the above indicators cannot be met, multi-dispersed aerosol (such as PSL, DEHS, DOP, etc.) should occur. Use laser particle counter or HEPA filter downstream 20-30mm away from the filter surface, scan along the whole surface, border and frame joints, etc. The scanning rate is 20-30mm/s.

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