Measurement uncertainty in use
As the calibration of a scale represents a snapshot, a statement must be taken how the measuring instrument behaves at the point of use and how the measurement uncertainty is changing. Because in the daily use of a scale, the measurement uncertainty increases due to various influences. These influences must be recorded and classified.
...and it goes like this:
Assuming the same environmental conditions (breeze, shocks,...) dominating at the time of calibration at the location of the balance and the estimated room temperature fluctuations of X Kelvin (°C) associated with one of scale temperature coefficient (X • 10-6 / K) to a particular use accuracy. The determination of these use accuracy is according to EURAMET/cg-18.