The present guideline describes the sampling and analysis of phosphoric acid esters in indoor air, in test chamber air and in house dust by gas chromatography/ mass spectrometry. Both principle methods of the low resolution mass spectrometry and the high resolution mass spectrometry are described. Phosphonous acid esters and thio- and dithiophosphoric acid esters are not considered. The methods described in this guideline are not suitable for determination of phosphoric acid esters in materials.