Manufacturers of measurement instruments calibrate their meters in their own calibration facilities. Of course, the purchasers of a meter must trust the facility and the measurement results. As an independent and internationally-recognised measurement institute, VSL can test the facility’s quality and determine the measurement uncertainties. From this there follows a VSL CMC certificate.
CMC stands for ‘Calibration and Measurement Capability’, in other words the best achievable measurement uncertainty of an (almost) ideal measurement instrument under normal operational conditions from a calibration test facility.
What is investigated?
This certification restricts itself to the technical performance of the calibration facility. In this, all vital components are checked:
- are all the instruments used traceable to internationally-accepted standards?
- are the calibration models (equations) correct?
- are procedures present for maintenance and use of the calibration or test facility?
The Calibration and Measurement Capabilities (CMC) are calculated according to JCGM 100:2008, “Evaluation of measurement data - Guide to the expression of uncertainty in measurement”.
Every two years, a technical audit is conducted to determine whether the calibration or test facility is still working within the specified CMC values. Part of this audit is to witness all the activities in the calibration or test facility.
Certificate and traceability
After the inspection, you receive a VSL certificate containing the calibration facility’s measurement uncertainty and a manual about traceability. It can be demonstrated with this certificate that the uncertainty claim at the time of the evaluation was achieved and that this can be achieved for a period of two years, providing the procedures are followed. VSL cannot be held responsible for the tests or calibrations that are conducted at the facility concerned or for the results that arise from them. The VSL certificate only shows that the facility can function within the measurement uncertainty values stated on the certificate.
Use of VSL logo
Companies with a VSL CMC certificate may display the VSL logo with the text ‘CMC certified’ on calibration certificates and reports. This is only permitted for the results of calibrations that were calibrated or tested using the certified facility. For more information click here.
Click here for an overview of the calibration or test facilities of companies that already possess a VSL CMC certificate.