When a dispute arises from a material supplier, the customer and supplier should perform comparative tests to determine if there is a statistical bias between the tests. Each side should take a group of test specimens that are as homogenous as possible from the material in question. The fabric specimens should be assigned at random in equal numbers for each laboratory to test. The average results from both testing’s should be compared. If a bias is found after comparing results, the cause must be investigated and corrected or the purchaser and supplier need to consider the bias when interpreting the test results of the material in question.