This part of ISO 16000 specifies a test method for the sampling and analysis of the phosphoric acid esters in indoor air and in test chamber air through gas chromatography/mass spectrometry. Both principle methods of the low-resolution mass spectrometry and the high-resolution mass spectrometry are described.The methods described in this part of ISO 16000 are not suitable for the determination of the phosphoric acid esters in materials.NOTE ISO 16000-6 can be applied for the determination of the more volatile compounds covered by this standard.