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FED-STD-209E

FED-STD-209 E "Airborne Particulate Cleanliness Classes in Cleanrooms and Cleanzones" was a federal standard concerning classification of air cleanliness, intended for use in environments like cleanrooms.The standard based its classifications on the measurement of airborne particles.The standard was canceled on November 29, 2001 by the United States General Services Administration (GSA).