Overview
EN ISO 14644-8:2022 - Cleanrooms and associated controlled environments: Assessment of air cleanliness by chemical concentration (ACC) defines standard methods to assess and specify airborne chemical contamination in cleanrooms and controlled environments. The document sets out typical assessment processes, an ISO-ACC descriptor format, and a protocol covering test methods, analysis and time‑weighted factors to determine grading levels of air chemical cleanliness. It applies where airborne chemical substances pose a risk to product, process or equipment and addresses ACC concentrations in the range given in the standard. It does not classify surface chemical contamination.
Key topics and requirements
- ISO-ACC grading levels: Framework to specify maximum allowable airborne concentrations for individual chemicals, groups or contaminant categories (expressed as an ISO-ACC level N).
- Assessment protocol: Procedures for testing, monitoring and reporting ACC, including guidance on demonstrating compliance and preparing a test report.
- ISO-ACC descriptor format: Standardized way to specify ACC requirements (chemical species, limits, sampling strategy, time weighting).
- Test methods & analysis: Guidance on typical measurement and analytical techniques (see Annex C for examples).
- Consideration factors: Parameters to consider when planning ACC assessment - generation sources, transport, sorption, operational conditions and separative devices (Annexes A and D).
- Informative annexes:
- Annex A: Parameters for consideration
- Annex B: Typical contaminating chemicals and categories
- Annex C: Typical methods of measurement and analysis
- Annex D: Specific requirements for separative devices
- Scope limits: Intended only where airborne chemical contamination is a risk; it does not describe contaminant chemistry in depth nor give surface contamination classification.
Applications and who uses it
EN ISO 14644-8:2022 is used by organizations that need to control airborne chemical contamination to protect sensitive products, processes or equipment. Typical users:
- Cleanroom and contamination-control engineers
- Quality assurance and regulatory compliance teams
- Facilities managers for pharmaceuticals, medical devices, microelectronics/semiconductor, aerospace, optics, photovoltaics, displays, LEDs, coatings, vacuum technology and related industries
- Test laboratories and third-party auditors performing ACC monitoring and validation
Practical uses include specifying ACC acceptance criteria, designing monitoring programs, selecting sampling and analytical methods, supplier and material qualification, and documenting compliance for audits or regulatory submission.
Related standards
- ISO 14644 series (airborne particulate classification and cleanroom design/operation)
- ISO 14644-1 (air cleanliness by particle concentration)
- ISO 14698 series (biocontamination control)
Using EN ISO 14644-8:2022 helps integrate chemical cleanliness into broader cleanroom specifications and contamination-control strategies.