ISO 14644

ISO 14644 Standards were first formed from the US Federal Standard 209E Airborne Particulate Cleanliness Classes in Cleanrooms and Clean Zones. The need for a single standard for cleanroom classification and testing was long felt. After ANSI and IEST petitioned to ISO for new standards, the first document of ISO 14644 was published in 1999, ISO 14644-1.

In 2000, ISO 14644-2 was published, which began the process of FED-STD-209E being canceled. On November 29, 2001, the document was canceled and superseded by ISO 14644-1 and ISO 14644-2.

ISO 14644-1 covers the classification of air cleanliness in cleanrooms and associated controlled environments. Classification in accordance with this standard is specified and accomplished exclusively in terms of concentration of airborne particulates. The document was submitted as an American National Standard and has been adopted as ANSI/IEST/ISO 14644-1:1999 in the United States, following the cancellation of FED-STD-209E.

Part 2 specifies requirements for periodic testing of a cleanroom or clean zone to prove its continued compliance with ISO 14644-1 for the designated classification of airborne particulate cleanliness. It also specifies requirements for the monitoring of a cleanroom or clean zone (installation) to provide evidence of its continued compliance with ISO 14644-1 for the designated classification of airborne particulate cleanliness. It became an International Standard following the cancellation of FED-STD-209E. In the United States in 2000 it was adopted as ANSI/IEST/ISO 14644-2:2000.

This part specifies test methods for designated classification of airborne particulate cleanliness and for characterizing the performance of cleanrooms and clean zones. These test methods are specified in the document for two different types of cleanrooms and clean zones; unidirectional flow and nonunidirectional flow.

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