Users of the current ISO 14644 cleanroom Standards are advised to become familiar with the new Draft International Standard (DIS) versions of ISO 14644-1 and 14644-2, released last December and available from the Institute of Environmental Sciences and Technology (IEST). Cleanroom professionals and others whose business operations are likely to be affected by changes in these documents are invited to submit comments on the new documents through April 15, 2011. IEST is the Secretariat for ISO Technical Committee (ISO/TC 209): Cleanrooms and associated controlled environments.

The key differences between ISO 14644-1:1999 and the new DIS version relate to a new principle for selecting cleanroom sample locations; a statistical sampling method is now required, and as a result, statistical testing of the data is no longer necessary. This approach reportedly allows for different concentration levels in different parts of the cleanroom and is designed to ensure with a given statistical confidence that at least 90% of the cleanroom area complies with the maximum particle concentration.

The contamination control community now finds itself choosing between the two versions of the cornerstone ISO cleanroom Standards, both of which may be used as trade reference per agreement between customers and suppliers. To help users of these Standards understand the changes in the new DIS versions, develop comments on those changes, and choose which version of the Standards to use as a reference, ISO/TC 209 recommends reading a peer-reviewed paper published in January as a special edition of the Journal of the IEST. Authored by members of the Working Group that developed the new Draft International Standards, this paper details the statistics behind the revised methods in ISO/DIS 14644-1 and ISO/DIS 14644-2.

Public comments will be accepted at www.iest.org/ISODIScomments through April 15, 2011. Comments will be submitted to the voting members of the US Technical Advisory Group (TAG) to ISO/TC 209 for consideration.

Source: IEST