AATCC 97:2020 pdf download.Test Method for Extractable Content of Textiles
10. Precision and Bias
10.1 Interlaboratory Study. A limited study was conducted in 2005 to estimate the precision of the Soxhiet and accelerated solvent extraction procedures and their relative bias. The study consisted of three laboratories, three fabrics and two operators per laboratory. The fabrics used included a 100% cotton bleached fabric, a 50/50 cotton/polyester greige fabric and a 100% cotton greige fabric. An accelerated solvent extractor made by Dionex Corporation, Sunnyvale, California was used in the study. Two determinations were conducted by each operator for each combination of test procedure and fabric. Averages and standard deviations for total extractable content are shown in Table I. Based on the limited data set on which this precision and bias statements have been made, users are cautioned when making critical decisions.
10.1.1 Analysis. The analyses used in this precision and bias statement are based on an analysis of all fabrics within each extraction method. The decision to conduct the all-fabric analysis was made based on the small study size and the resuits of the single-material computations. Variance components rcportcd here were estimated using ASTM D2904-97, Annex A 1. Details on the data and analysis can be obtained by contacting the AATCC Technical Center. Precision is reported in ternm of critical differences. Calculations outlined in ASTM D2906- 97 (2002) were used to compute the one- sided critical differences between two means for sample sizes.
10.1.2 Variance Components. Soxhiet Procedure. The variance components calculated for the Soxhlet procedure are reported in Table II. All metrics reported in this section are in units ot°/o of total extracted content.
10.1.3 Critical Differences—Soxhlet Method. The 95% critical differences calculated for the Soxhiet method are shown in Table Ill.
10.1.4 The variance components for the accelerated solvent extraction procedure are reported in Table IV.
10.1.5 The subsequent 95% critical differences estimated for the accelerated solvent procedure are shown in Table V.
10.2 Bias. The amount of extractable matter on a textile material is dependent on the extraction procedure used. Therefore, it is not possible to determine abso solvent) is used, note the solvent on the test re-port.AATCC 97 pdf download.