What is a proficiency testing (PTP) / interlaboratory comparison (ILC) ?

     A proficiency testing program (or interlaboratory comparison or round robin test) consists in testing the same samples by different laboratories and in comparing the results. Three different objectives can be pursued: validate a test method and determine the uncertainty of results, determine the characteristics of a product intended for be used as a reference material, assess the reliability of the test results of the participating laboratories.

The proficiency testing programs organised by CompaLab pursue the latter goal on tests concerning metals (steels).


The 5 good reasons to participate in a proficiency test :

  1. An error on a test result can have serious consequences and can be very expensive
  2. Participating in a proficiency test is a very effective method of assessing a laboratory's competence
  3. Participation in a proficiency test is required for accreditation
  4. You and your customers need complete trust in the reliability of your test results
  5. The cost of participating in a proficiency test is very low compared to the trust it provides and the costs generated by unreliable tests


The participation to an interlaboratory comparison supposes the acceptance of general conditions for participation, that detail mutual commitments of the provider and the participants.