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Standard Interpretation

Standard: 2003 NELAC
Section: Appendix C.1
Link to relevant standard


I would like to have interpreted Appendix C - Demonstration of Capability C.1 paragraph 6. and step a). The test methods we are applying for NELAC accreditation are the EPA 500 methods for SDWA compliance testing. These methods are mandatory test methods by both State and Federal regulation. In paragraph 6 it states "following steps shall be performed if required by mandatory test method or regulation". So my question is: If a test method specifically has the IDCs to be completed by use of an LFB (not a QCS obtained from an outside source) then shouldn't NELAC recognize these IDCs as acceptable for accreditation?

I also interpret the language at a) that the QCS to be used for the DOC only needs be what we usually refer to as second source if the stock standards were prepared within the laboratory and not acquired through an outside source.

I appreciate your time with this question.


(Quality Systems Expert Committee/NELAP Board, 10-25-08)

The outside source cited in C.1 a) meant a source other than calibration standards. This is consistent with the definition of Quality Control Sample, which may be a Certified Reference Material, quality system matrix fortified by spiking, or actual samples fortified by spiking. If the laboratory's LFB meets the definition of a Quality Control Sample, the lab would be in compliance.