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Standard Interpretation



Standard: 2009 TNI
Section: V1M2, Section 5.5.13.1


REQUEST:

This section requires verification of volumes of volumetric dispensing devices (except Class A Glassware) if quantitative results are dependant on their accuracy. Historically, this section has been interpreted to include disposable pipettes and plastic tubes used for measuring sample volumes or final volumes after digestion. Section 5.5.13.1.d [editor's note - this is actually 5.5.13.1 e] appears to require quarterly checks of these devices. Quarterly checks seem excessive when the items are one use items. Once per lot number seems more reasonable and would be similar to receiving a certificate from the manufacturer about the accuracy of a particular lot number.

Since these are disposable, one use items. would verification of the volume once per lot number be acceptable?

TNI FINAL RESPONSE:

A verification of one pipette or tube per lot would meet the requirements stated in Sections 4.6.2 and 5.5.2.