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Standard Interpretation

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


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 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 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

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


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.