Abstract: 4-aminoazobenzene is included in the list of aromatic amines banned for use in textiles in GB 18401/2010, a compulsory standard newly released in China. This article explained the campaign for testing the proficiency of determining 4-aminoazobeneze in textiles, which were participated by 30 laboratories. It analyzed the reasons that cause some labs failed to pass the test and put forward some suggestions on improving 4-aminoazobenzene determination techniques.

Key words: proficiency test; 4-aminoazobenzene; textiles