Interlaboratory comparison material homogeneity testing

Abstract

The homogeneity of fertilizer samples for interlaboratory γ-ray spectrometry comparison was tested by determination of the total γ count rate and the count rates for two 238U γ lines, one 40K line and one common 235U and 226Ra line. Homogeneity testing was accomplished by determination of the minimum, maximum, mean and standard deviation for each parameter and comparison of their standard deviations with predefined tolerances, by Cochran's test, and by a one-way ANOVA. The standard deviations were all less than these tolerances. All samples passed Cochran's test and the one-way ANOVA test for homogeneity.