MEASURAND : Mass fraction of Al in silicon nitride powder NOMINAL VALUE : 824 mg/kg
The key comparison reference value, xR, is computed as the arithmetic mean of the participant's results. Its expanded uncertainty (k = 2) is UR = 2uR, where uR is the standard deviation of the mean.
xR = 824.4 mg/kg, UR = 15.6 mg/kg
The degree of equivalence of laboratory i relative to the key comparison reference value is given by a pair of terms, both expressed in (mg/kg): Di = (xi - xR) and its expanded uncertainty (k = 2) Ui= (ULab i2 + UR2)1/2.
The degrees of equivalence between pair of laboratories have not been computed for this key comparison.