3rd edition of procedure on estimation and expression of measurement uncertainty in chemical analysis available in English

When the result of a chemical analysis is presented in an analytical report it is recommended that it should always be reported as a numerical result. For the result to be complete, the measurement uncertainty of the analysis should also be included. In many cases, a result can be very hard to interpret unless accompanied by its uncertainty.

In this updated version of the procedure, guidance on how to handle bias / systematic errors in relation to measurement uncertainty is included. The principles described in Nordtest TR 537 for environmental analyzes have been introduced in the NMKL procedure and examples showing how these calculations are to be performed have been added. Whether one can or should correct for systematic errors is a complex issue, and a new section has been added to explain his. Additionally, minor restructuration and update of references have been undertaken.

A scandinavian version of this 3rd edition will follow.