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Standard Interpretation

Standard: 2003 NELAC
Section: (d)


I could not find this same paragraph in the new 2009 standard documents posted on the TNI site.

My question pertains to the interpretation of this statement in the 2003 NELAC standard and how it applies to the 2009 TNI standard. We have been informed that Environmental lab auditors are now requiring labs to use a second vendor for their second source calibration standards even when use of a second manufactured lot from the same vendor is allowed by both the 2003 NELAC and 2009 TNI standards. We have even heard that second source from a second manufacturer raw material prepared by the same vendor is being noted as non-compliant in some instances.

What is the interpretation of what this standard requires of labs where it applies to non-DoD programs with regard to the following options:
1. Same vendor/supplier - two independently prepared lots from the same raw material.
2. Same vendor/supplier - two independently prepared lots from different manufacturer raw materials when available.
3. Two different vendor/suppliers for each of the primary and secondary lot standards.

Thank you


(Quality Systems Expert Committee and NELAP AC, 10-4-14)

The purpose is to verify that the standards used for calibration have been properly prepared. The verification standard must be prepared independently from the calibration standard(s). The best option is standards from two different vendors; alternatively, standards from the same vendor but different lot numbers. While the original source (manufacturer) of the neat standard is important, the standard stresses independent preparation.