The GUM Supplement 1 and the Uncertainty evaluations of eMc Measurements

The "Guide to the expression of uncertainty in measurement" (GUM) provides the theoretical frame- work which is worldwide adopted for the evaluation of measurement uncertainty, including the application to calibration and testing. The GUM uncertainty approach has however fundamental limits. If these limits are exceeded the results produced are no longer valid. The Supplement 1 to the GUM (GUMS1) describes a numeri- cal technique aimed at extending the validity of the uncertainty evaluations to cases where the application of the GUM does not produce reliable results. The scope here is to point out the conditions under which it is nec- essary to make use of the GUMS1 technique. Explicit reference to Electromagnetic Compatibility (EMC) mea- surements will be made.