4.4. Expanded uncertainty

Brief summary: The probability of roughly 68% that is provided by the standard uncertainty is often too low for the users of measurement uncertainty. Therefore measurement uncertainty is presented to customers mostly as expanded uncertainty, U. Expanded uncertainty is calculated from the standard uncertainty by multiplying it with a coverage factor, k.

In the case of the pipetting example the k = 2 expanded uncertainty is found as follows:

Expanded uncertainty at k = 2 level is the most common way of expressing uncertainty of measurement and analysis results.

Calculating the expanded uncertainty
http://www.uttv.ee/naita?id=17579

https://www.youtube.com/watch?v=tBwkuL0ap14