ASTM D6674-01(2013)

4.1 Proficiency testing is a means of securing estimates of the variability of results obtained by different laboratories testing homogeneous materials taken from batch samples when following procedures prescribed in a specific test method.

4.2 This proficiency test program is to be considered a full-scale interlaboratory test, in which a reasonably large number of laboratories participate by testing a series of materials using one or more operators per laboratory and report the data for analysis.

4.3 The statistical data generated by this practice provide information needed to exhibit participation in a formal proficiency test study.

4.4 All data are submitted to the program coordinator at ASTM Headquarters for the preparation and distribution of the proficiency testing program reports. All laboratory data are confidential with no disclosure of lab identity except for each participant's own laboratory. Published reports contain all laboratory test data (coded), statistical analysis of test data, charts plotting test results versus lab code, and other information.

1.1 This guide outlines the Proficiency Test Program for Fabrics. Elements for planning the proficiency test program, selecting the sample fabrics to be used, the testing protocol, and the calculations for the data to be reported are included in this practice.

1.2 The planning of the proficiency test program requires a general knowledge of testing of textile fabrics and statistical principles included in the analysis of the data.

1.3 This guide is designed to meet the quality systems proficiency and competence requirements of participating laboratories. This program is not accredited to any international standard.

1.4 The instructions in this guide follow the logic of full scale laboratory tests as described in Practice D2904 and Guide E1301, except with this new guide placing its emphasis on proficiency testing.

1.5 Procedures given in this guide are applicable to methods based on the measurement of discrete measurement data and grades or scores.