Metrological Reference
Formal designation for the Guide to the Expression of Uncertainty in Measurement maintained by the Joint Committee for Guides in Metrology. Procedures established in jcgm 100 2008 guide the propagation of uncertainties through complex measurement models using Taylor series expansion. The document assumes that a measurand can be characterized by a single value plus or minus an uncertainty.
It provides a universal language for reporting the quality of a measurement.
Calculation Principle
Probability distributions are assigned to each input quantity to represent the knowledge about its true value. Adopting the jcgm 100 2008 methodology ensures that the evaluation of uncertainty is consistent and scientifically defensible. Sensitivity coefficients are derived from partial derivatives of the measurement function.
Type Evaluation
Estimating uncertainty involves evaluating both the random effects and the systematic effects as described in jcgm 100 2008. Random components are often determined from the standard deviation of repeated measurements. Systematic components are usually estimated from calibration data or physical constants.
Global Adoption
National metrology institutes around the world adopt jcgm 100 2008 to ensure that their primary standards are internationally recognized and equivalent. Compliance with this standard allows for the mutual recognition of calibration certificates across borders. Global agreement forms the basis for the iso seventeen zero two five accreditation requirements.
