IEST offers new ISO cleanroom classification and monitoring standards

摘要

The IEST has announced the international approval of the new revisions to the flagship cleanroom standards ISO 14644. The revised standards were approved by a majority of the 20 member nations participating in the ISO/TC 209 final vote. They will be available from IEST following editorial revision and international translation. The revision efforts by the lead ISO/TC 209 Working Group lasted more 10 years, with the ISO Technical Management Board providing a second extension of the drafting period. A major focus in revising ISO 14644-1 (1999) was to develop a refined statistical approach regarding the selection and number of sampling locations. The underlying assumption in the 1999 version held that particle counts follow a similar distribution across the room. The new revision discards the previous assumption to allow more accurate sampling where particle counts may vary in a more complex pattern.