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What is an ILC/PTP (proficiency testing) ?

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An inter laboratory comparison (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.

Inter laboratory comparions organised by CompaLab pursue the latter goal: proficiency testing on tests concerning metals (steels), in accordance with ISO 13528.

Because an error in a test result can have serious consequences and can be very expensive, because participate to a proficiency test is a very efficient method to assess the competence of a laboratory, and because it is required for accreditation, because you need a total confidence in your test results, because you need to demonstrate to your customers that your test results are reliable, and because the cost of a participation to a proficiency test is very low compared to the confidence it provides and compared with the costs of non-reliable tests, you should participate to proficiency testing programs.

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

Image mean valueImage standard deviation

Example of verification of the normality of the distribution of mean value and repeatability of the results of participants.


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