Standard Test Method for Extractable Matter in Textiles
In case of a dispute arising from differences in reported test results using this test method for acceptance testing of commercial shipments, the purchaser and the supplier should conduct comparative tests to determine if there is a statistical bias between the laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using appropriate statistical analysis and a probability level chosen by the two parties before the testing begins. If a bias is found, either its cause must be found and corrected, or the purchaser and supplier must agree to interpret future test results with consideration to the known bias.
CONTINUE READING ON www.astm.org