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Standard Interpretation

Standard: 2003 NELAC
Section: Appendix F.2.1, F.2.2, F.3
Link to relevant standard


I am confused about the PT requirements for labs doing WET analysis. The only 'true' PT is the DMRQA - but it runs longer than 45 days - which doesn't meet F.2.2 requirements. I need to know will the DMRQA be allowed and counted as a PT until such a time as the PT providers have other PTs available?


(Proficiency Testing Executive Committee / NELAP Accreditation Council, 1-x-11)

While the DMRQA study containing the WET PT is open for a period longer than 45 days, the laboratory must complete the analysis of the WET PT sample within 45 days of sample receipt in order for the WET PT result to be used to meet 2003 NELAC standard requirements. The laboratory would have up to 45 days from sample receipt to analyze the WET sample and then the remainder of the DMRQA study period to report the WET PT analytical results to the PT provider.