ISO 12500

… the „most controversial standard“ of compressed air treatment technology

The subject of the ISO 12500 series are test methods for water separators and compressed air filters at laboratory and defined operating conditions (test conditions). The target is to generate standardized and thus comparable product performance figures, allowing the comparison of products in regards to their performance or economic efficiency.

ISO 12500-1
ISO 12500-2
ISO 12500-3
ISO 12500-4


All tests are performed at one specific working point of the compressed air filter and thus are not representative for the performance of the filter at real life working conditions deviating from the defined test conditions. Thus typically there is no relation between an ISO 12500 test result and the compressed air purity achieved by the filter in a real life compressed air system.


Most ISO 12500 standards refer to test methods of the ISO 8573 series.



  • The defined test methods of ISO 12500 are more a kind of „worst case scenarios” for compressed air filters and thus offer only a low benefit for real life applications
  • Accordingly, the determined results are poorly applicable up to misleading (without specific knowledge may lead to a wrong assignment of products)
  • Furthermore, ISO 12500 demands many extensive and several times repeated tests, resulting in enormous test efforts
  • Consequently, the ISO 12500 series in its actual edition suffers from a poor acceptance
  • Primarily ISO 12500-1 and ISO 12500-2, but also ISO 12500-3 and ISO 12500-4 require an extensive revision​​​​​​​


Standards are protected by copyright .

Thus they are distributed exclusively, e.g. in Germany by Beuth-Verlag (