Attached is a couple of documents that clarifies the usage or disposition of NIST numbers in the certs. It is not a requirement to place that number in the certification.
Q. - what should auditors (Internal / External) use to meet the requirements of 7.6?
Where necessary to ensure valid results, measuring equipment shall
a) be calibrated or verified, or both, at specified intervals, or prior to use, against measurement standards traceable to international or national measurement standards; where no such standards exist, the basis used for calibration or verification shall be recorded (see 4.2.4);
Q. - what should auditors (Internal / External) use to meet the requirements of 7.6?
Where necessary to ensure valid results, measuring equipment shall
a) be calibrated or verified, or both, at specified intervals, or prior to use, against measurement standards traceable to international or national measurement standards; where no such standards exist, the basis used for calibration or verification shall be recorded (see 4.2.4);