The Institute of Environmental Sciences and Technology (IEST) recently announced that the International Organization for Standardization (ISO) has published ISO 14644-8, Cleanrooms and associated controlled environments – Part 8: Classification of airborne molecular contamination. IEST serves as Secretariat for ISO Technical Committee 209, which developed the International Standard as part of a series of documents to serve the needs of the global contamination control community.

The new document is designed for use in a wide range of industries-such as microelectronics, pharmaceuticals, medical devices, and others-that may be adversely affected by airborne molecular contamination (AMC). It assigns ISO classification levels to specify the limits of AMC concentrations within cleanrooms and associated controlled environments where the product or process is at risk from such contamination.

According to the IEST, the ISO standard covers the classification of AMC in terms of specific chemical species (individual, group, or category) and considers concentrations of AMC between 100 and 10-12 g/m3 under cleanroom operational conditions. The document provides a protocol to include test methods, analysis, and time-weighted factors within the specification for classification. The annexes cover topics such as parameters for consideration, typical contaminating chemicals and substances, typical methods of measurement and analysis, and considerations of specific requirements for separative enclosures.

ISO 14644-8 is available from the IEST. For more information, visit www.iest.org.