Normative Foundations

ConCertainty is based on recognized international and national standards for determining measurement uncertainty and laboratory accreditation. This page gives a brief overview of the relevant standards and their role in ConCertainty.

GUM – Guide to the Expression of Uncertainty in Measurement

The GUM is the fundamental international document for determining and stating measurement uncertainties. It describes the general principles and methods on which the determination of measurement uncertainty is based.

In ConCertainty, the GUM forms the conceptual basis for calculating the combined and expanded measurement uncertainty.

DIN ISO 11352 – Water Analysis

DIN ISO 11352 describes the estimation of measurement uncertainty based on validation and quality assurance data. Among other things, it defines the terms and calculation methods for reproducibility and comparability used in ConCertainty.

ConCertainty calculates the measurement uncertainty according to the procedure described in DIN ISO 11352 – based on series of measurements (reproducibility) and comparison values from certified reference materials or interlaboratory comparison participations (comparability).

ISO/IEC 17025 – Competence of Testing and Calibration Laboratories

ISO/IEC 17025 specifies the general requirements for the competence, impartiality, and consistent operation of laboratories. It is the basis for the accreditation of testing and calibration laboratories.

ConCertainty helps laboratories meet the requirements of ISO/IEC 17025 regarding the determination and documentation of measurement uncertainties.