Frequently asked questions
Assessing electrical measurement uncertainties

Is it compulsory to use or follow the method developed in the GUM?

No, especially in industry, where a company can devise and apply a simpler method, or one better suited to the specific measurements required for its production processes. On the other hand, knowledge of the GUM method and its application are essential when applying for COFRAC testing or calibration accreditation.

Is the determination of measurement uncertainty mandatory for a company manufacturing toleranced products, such as resistors whose values are marked with a tolerance of ± 1%?

These resistors are certainly checked by sampling, and it is essential that the uncertainty of the measurements carried out for these checks is known. It is desirable that measurement uncertainty be less than or equal to 0.1% for 1% resistors (notion of capability)....