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Standard Interpretation

Standard: 2016
Section: V1M2, Section


d) Temperature measuring devices shall be calibrated or verified at least annually. Calibration or verification shall be performed using a recognized National Metrology Institute traceable reference, such as NIST, when available.

Question: do reference thermometers need to be calibrated annually? These are traceable to NIST.


As long as the reference thermometer is not being used as a piece of support equipment such as described in c, a reference thermometer is a reference standard as described in and would need to be calibrated before and after any adjustment, and in accordance with the lab’s documented procedure.