Proficiency Testing Information

According to Nevada law (NAC 445A.0634), if a PT for an analyte in a matrix exists from any approved provider, it must be successfully analyzed in order to receive certification for that parameter. So for every method/analyte/matrix combination requested you must submit PT results.

What if a PT does not exist for an Analyte?

If you do not believe a PT exists for a given analyte in a given matrix there are several steps to take. The first is to check with various PT providers and then if PTs are still not found check with a Nevada LCO. If a PT is not available then we require a demonstration of capability (DOC) for those specific analytes (please review Chapter 5 Appendix C of the 2003 NELAC Standard if unsure of requirements for a DOC). 

If the method requires a specific preparation method be used in conjunction with measuring an analyte of interest, submit both SOPs (1311/8260B) for review. All SOPs should be reviewed on an annual basis.

How many PTs should I be running?

We require that laboratories pass two of the last three PTs in the past 18 months for each method/analyte/matrix combination requested. This equals out to about one PT study every six months. A missed PT study will be counted as a failure!

If you fail a PT and elect to do a quick turnaround then there must be at least 15 calendar days apart from the closing date of one study to the shipment date of another study for the same field of proficiency testing.

Who do I send my PT results to?

PT results must come to us at directly from your PT vendor. The results must be sent both as a PDF file and as a CSV file in Utah format.

What happens if I fail PTs?

If you fail one PT for a given parameter, figure out what went wrong and document your associated corrective action. Submit a copy of your corrective action to Nevada Laboratory Certification Program (NVLaboratoryCertification [at]

If you fail two out of the last three PTs your Nevada certification for that parameter is no longer valid whether we contact you or not! If you fail two consecutive studies, then you must pass two consecutive studies to be in compliance!

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