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Standard Interpretation



Standard: 2009 TNI
Section: V1M2, Section 5.5.13.1 (e)


REQUEST:

How encompassing is the universe of "volumetric dispensing devices (except Class A glassware and glass microliter syringes)" needing quarterly checks for accuracy? Specifically, do graduated cylinders, glass to-deliver pipets, and other garden-variety glassware, which are not Class A, need to be checked quarterly?

NELAC 5.5.5.2.1.e read, "Mechanical volumetric dispensing devices including burettes (except Class A glassware) shall be checked for accuracy on a least a quarterly use basis." The introductory paragraph to NELAC 5.5.5.2.1.e includes "... volumetric dispensing devices (such as Eppendorf or automatic dilutor/dispensing devices)." Both of these examples are mechanical volumetric dispensing devices and supported "mechanical" in NELAC 5.5.5.2.1.e.

TNI V1M2-5.5.13.1.e does not include the word "mechanical" which previously appeared in NELAC 5.5.5.2.1.e. However, the introductory paragraph to TNI V1M2-5.5.13.1 is identical to that in NELAC 5.5.5.2.1 (i.e., continues to includes two examples of mechanical volumetric dispensing devices).

TNI FINAL RESPONSE:

Any volumetric dispensing devices (with the noted exception of Class A glassware and glass microliter syringes) must be verified on a quarterly basis when the volume delivered is used quantitatively to meet the accuracy of the analysis.