Statistical processing the interlaboratory testing results of grain-size distribution of stone coal from the Coal Mine Avramica

Abstract

This work presents the results of interlaboratory testing the grain-size distribution of stone coal from the Coal Mine Avramica. Tests were carried out on representative samples of coal. The results were processed by two ways: numerical method - Cochran's test of accuracy and graphic interpretation - Calculating the z value in accordance with the Standard SRPS ISO 5725-2 [1]. The followings were calculated: variance of repeatability variance Sr2; interlaboratory variance SL 2 and reproducibility variance SR 2. The samples distributed to all participating laboratories using the method of sharing.

Keywords

• statistical processing of the results
• stone coal
• grain-size distribution