This International Standard describes the gas chromatographic determination of 15 chlorophenols (2,3-, 2,4- 2,5-, 2,6-, 3,4- and 3,5-dichlorophenol; 2,3,4-, 2,3,5-, 2,3,6-, 2,4,5-, 2,4,6- and 3,4,5-trichlorophenol, 2,3,4,5- and 2,3,4,6-tetrachlorophenol and pentachlorophenol) in soil samples. This method can also be applied to other solid samples such as sediments and solid wastes. This International Standard describes an acid-base liquid extraction, followed by acetylation and then liquid/liquid extraction. Determination of mass concentration is then carried out by gas chromatography and electron-capture detection. This method is applicable to chlorophenols at the lowest mass concentrations ranging from approximately 0,01 mg/kg to 0,05 mg/kg depending on the component sensitivity and the quantity of sample used. In some cases complete separation of isomers cannot be achieved, in which case the sum is reported (for instance 2,4- and 2,5-dichlorophenols).