The application of the ventilation equations to cleanrooms – Part 2: Decay of contamination
نویسندگان
چکیده
This article is the second of a three-part series that investigates the application of the ventilation equations to designing and testing cleanrooms. This part is concerned with the decay equation. The recovery test, described in ISO 14644-3 (2005) is discussed, and improvements recommended. The application of the decay equation to the ‘clean up’ requirement given in the EU GGMP (2008) is also discussed. Finally, a method is considered that calculates the time needed for airborne contamination in cleanroom areas to decay to acceptable concentrations.
منابع مشابه
Decay of airborne contamination and ventilation effectiveness of cleanrooms
This article reports an investigation into the ability of the air supply in non-unidirectional cleanrooms to aid recovery from episodes of airborne contamination, and minimise airborne contamination at important locations. The ISO 14644-3 (2005) recovery test, which measures the rate of decay of test particles, was assessed and a reinterpretation of the test results suggested. This allowed air ...
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