This International Standard specifies a method for the determination of volatile organic compounds (see Table1). This comprises, for example, halogenated hydrocarbons, trihalogenated methanes, gasoline components (such as BTEX, MTBE, and ETBE), naphthalene, 2-ethyl-4-methyl-1,3-dioxolane, and highly odorous substances like geosmin and 2-methylisoborneol in drinking water, ground water, surface water, and treated waste water, by means of headspace solid-phase micro-extraction (HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS). The limit of determination depends on the matrix, on the specific compound to be analysed, and on the sensitivity of the mass spectrometer. For most compounds to which this International Standard applies, it is at least 0,01μg/l. Validation data related to a concentration range between 0,02μg/l and 2,6μg/l have been demonstrated in an interlaboratory trial. Additional validation data derived from standardization work show applicability of the method within a concentration range from 0,01μg/l to 100μg/l of individual substances. All determinations are performed on small sample amounts (e.g. sample volumes of 10ml). This method may be applicable to other compounds not explicitly covered by this International Standard or to other types of water. However, it is necessary to demonstrate the applicability for each case. Table1 Volatile organic compounds determinable by this method Name Molecular formula CAS registry no. d Molar mass g/mol Density kg/l tert-amyl methyl ether (TAME) C6H14O 994–05–8 102,17 0,76 benzene C6H6 71–43–2 78,12 0,88 bromobenzene C6H5Br 108–86–1 157,01 1,50 bromochloromethane CH2BrCl 74–97–5 129,38 1,99 bromodichloromethane CHBrCl2 75–27–4 163,83 1,98 n-butylbenzene C10H14 104–51–8 134,22 0,86 sec-butylbenzene C10H14 135–98–8 134,22 0,86 tert-butylbenzene C10H14 98–06–6 134,22 0,87 chlorobenzene C6H5Cl 108–90–7 112,56 1,11 2-chlorotoluene C7H7Cl 95–49–8 126,59 1,08 4-chlorotoluene C7H7Cl 106–43–4 126,59 1,07 dibromochloromethane CHBr2Cl 124–48–1 208,34 2,45 1,2-dibromo-3-chloropropane (DBCP) C3H5Br2Cl 96–12–8 236,33 2,03 1,2-dibromoethane C2H4Br2 106–93–4 187,86 2,18 dibromomethane CH2Br2 74–95–3 173,83 2,48 1,2-dichlorobenzene C6H4Cl2 95–50–1 147,00 1,30 1,3-dichlorobenzene C6H4Cl2 541–73–1 147,00 1,29 1,4-dichlorobenzene C6H4Cl2 106–46–7 147,00 1,25 1,1-dichloroethane C2H4Cl2 75–34–3 98,96 1,20 1,2-dichloroethane C2H4Cl2 107–06–2 98,96 1,25 1,1-dichloroethene C2H2Cl2 75–35–4 96,95 1,21 cis-1,2-dichloroethene C2H2Cl2 156–59–2 96,94 1,28 trans-1,2-dichloroethene C2H2Cl2 156–60–5 96,94 1,26 dichloromethane CH2Cl2 75–09–2 84,93 1,33 1,2-dichloropropane C3H6Cl2 78–87–5 112,99 1,16 1,3-dichloropropane C3H6Cl2 142–28–9 112,99 1,19 2,2-dichloropropane c C3H6Cl2 594–20–7 112,99 1,08 1,1-dichloropropene C3H4Cl2 563–58–6 110,97 1,19 cis -1,3-dichloropropene c C3H4Cl2 10061–01–5 110,97 1,23 trans-1,3-dichloropropene c C3H4Cl2 10061–02–6 110,97 1,21 ethylbenzene C8H10 100–41–4 106,17 0,86 ethyl tert-butyl ether (ETBE) C6H14O 637–92–3 102,17 0,73 2-ethyl-4-methyl-1,3-dioxolane C6H12O2 4359–46–0 116,16 0,90 2-ethyl-5,5-dimethyl-1,3-dioxane C8H16O2 768–58–1 144,21 0,88 geosmin C12H22O 16423–19–1 182,30 0,99 hexachlorobutadiene C4Cl6 87–68–3 260,76 1,67 isopropylbenzene (cumene) C9H12 98–82–8 120,19 0,86 4-isopropyltoluene (p-cymene) C10H14 99–87–6 134,21 0,86 2-methylisoborneol C11H20O 2371–42–8 168,28 0,97 methyl tert-butyl ether (MTBE) C5H12O 1634–04–4 88,15 0,74 naphthalene C10H8 91–20–3 128,17 1,14 n-propylbenzene C9H12 103–65–1 120,19 0,86 styrene C8H8 100–42–5 104,15 0,91 1,1,1,2-tetrachloroethane C2H2Cl4 630–20–6 167,85 1,55 1,1,2,2-tetrachloroethane C2H2Cl4 79–34–5 167,85 1,59 tetrachloroethene C2Cl4 127–18–4 165,83 1,62 tetrachloromethane CCl4 56–23–5 153,82 1,59 toluene C7H8 108–88–3 92,14 0,87 tribromomethane (bromoform) CHBr3 75–25–2 252,75 2,89 1,2,3-trichlorobenzene C6H3Cl3 87–61–6 181,45 1,68 1,2,4-trichlorobenzene C6H3Cl3 120–82–1 181,45 1,45 1,3,5-trichlorobenzene C6H3Cl3 108–70–3 181,45 1,87 1,1,1-trichloroethane C2H3Cl3 71–55–6 133,40 1,34 1,1,2-trichloroethane C2H3Cl3 79–00–5 133,40 1,44 trichloroethene C2HCl3 79–01–6 131,39 1,46 trichloromethane (chloroform) CHCl3 67–66–3 119,38 1,47 1,2,3-trichloropropane C3H5Cl3 96–18–4 147,43 1,38 1,2,4-trimethylbenzene (pseudocumene) C9H12 95–63–6 120,19 0,88 1,3,5-trimethylbenzene (mesitylene) C9H12 108–67–8 120,19 0,86 vinyl chloride C2H3Cl 75–01–4 62,5 1,88 b m-xylene a C8H10 108–38–3 106,17 0,86 o-xylene C8H10 95–47–6 106,17 0,88 p-xylene a C8H10 106–42–3 106,17 0,86 a Signals of substances may overlap in chromatograms as they might co-elute. b Density of liquid at boiling point (−13,4°C) c Refer to TablesF.1 and F.2 for validation data and additional information. d CAS: Chemical Abstracts Service.