For official access, the standard can be purchased or viewed through authorized distributors like Accuris Standards Store or Intertek Inform . ISO 14644-3
– The standard provides clearer criteria for when alternative procedures can be used, emphasizing that customer-supplier agreement must be documented and that alternative methods "do not necessarily provide equivalent measurements".
Many national bodies adopted the corrected version of ISO 14644-3:2019 as their own national standard in 2020 and 2021. For example: iso 146443pdf 2021
These are performed based on the specific requirements of the user or the nature of the process. For high-stakes environments (like sterile manufacturing), these are often mandatory.
To use an analogy: ISO 14644-1 is the "performance standard" (what the cleanroom must achieve), while ISO 14644-3 is the "methods standard" (how to demonstrate that performance). For official access, the standard can be purchased
– The 2019 edition no longer includes the airborne particle count for classification as a test method within Part 3, as this is now exclusively covered by ISO 14644-1. This change clarifies the boundary between the two standards.
Purchase through your country's ISO member organization for local pricing and support. A list of national member bodies is available on the ISO website. For example: These are performed based on the
Cleanrooms are often defined by their "ISO Class," a designation from ISO 14644-1