Charbon et coke — Échantillonnage mécanique — Partie 7: Méthodes pour la détermination de la fidélité de l'échantillonnage, de la préparation de l'échantillon et de l'essai

This document defines methods for estimating overall precision and for deriving values for primary increment variance which can be used to modify the sampling scheme to change the precision. Methods for checking the variance of sample preparation and testing are also described.

In this document, formulae are developed which link the variables that contribute to overall sampling precision.