Which statement about a Certified NIST-reference thermometer is accurate?

• A. It is a thermometer that has no traceability requirements.
• B. It is a thermometer certified against standards traceable to NIST and requires documentation.
• C. It is a thermometer used only for home use.
• D. It is a thermometer that does not require calibration.

Answer: (B)

A Certified NIST-reference thermometer is a high-accuracy standard instrument whose measurements are linked to national standards through a documented calibration chain. This means its calibration is traceable to NIST, and you carry a certificate or documentation showing the traceability, the calibration date, methods used, and the stated uncertainty. Regular calibration and verification are part of its use to ensure the thermometer stays within spec, which is essential for reliable reference measurements in a lab setting. It’s not a consumer/home device, and it does require calibration, so statements claiming no traceability or no calibration aren’t accurate.