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Standard Interpretation



Standard: 2003 NELAC
Section: 2
Link to relevant standard

REQUEST:

The SCM PT standard for TPH references HEM/SGT on the FoPT. HEM/SGT is a method defined analyte for method to 1664A. The scope and application section of 1664A says that it is for "surface and saline waters and industrial and domestic aqueous wastes". Therefore, the method has to be modified to be performed on solid and chemical materials. Is it appropriate to have a required PT for a non-standard method?

TNI FINAL RESPONSE:

(PT Board / NELAP Board, x-x-10)

The TNI PT Board does not get involved in questions concerning the appropriateness of methods for specific analytes. Accrediting bodies routinely accredit labs for "non-standard" methods and then require the analysis of PTs included on the FoPT tables. The general answer to your question is, yes, it is appropriate to have a required PT for a non-standard method.