The quality and performance of filters in cleanrooms play a crucial role in maintaining cleanroom classification and ensuring the purity of the air. An important component in the qualification of cleanrooms is checking that HEPA filters are leak-free to ensure that no impurities or particles can enter through leaks.

Leak-free filters

Checking that HEPA filters are leak-free is a crucial step in the qualification of cleanrooms. A distinction is made between terminal filters, or FFUs, and duct filters. In any case, the last filter before the actual clean room must be checked for holes in the filter material and for leaks in the filter frames. Only by complying with the relevant guidelines and standards can companies ensure that their cleanrooms meet the necessary cleanliness requirements and guarantee product quality.

In accordance with ISO 14644, the international standard for cleanrooms and associated facilities, filters must be checked regularly to ensure that they are leak-free. The standard specifies requirements for the test procedures and tolerance limits to ensure that the filters meet the necessary purity requirements.

VDI 2083, the guideline for protective measures in air pollution control, also specifies requirements for filters to be leak-free. It contains detailed guidelines for checking the filter and documenting test results.

In the pharmaceutical industry, the GMP guidelines for the manufacture of medicines are of crucial importance. Here, filters must be checked regularly in accordance with the requirements of the GMP guidelines to ensure that the air in the cleanroom meets the necessary purity requirements.


  • ISO 14644,
  • VDI 2083
  • GMP guidelines

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