ISO INTERNATIONAL STANDARD 9487 First edition 1991-08-15 Workplace air - Determination of vaporous aromatic hydrocarbons -. Charcoal tube/solvent desorption/gas chromatographic method Air des lieux de travail -- Determination des hydrocarbures aromatiques vaporeux -- Methode d'analyse par tube a charbon actifldésorption des solvants/chromatographie en phase gazeuse Reference number 1SO 9487:1991(E) Not for Resale without license from IHS ISO 9487:1991(E) Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards bodies (isO member bodies). The work of preparing International Standards is normally carried out through Iso technical committees, Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. international organizations, govern- mental and non-governmental, in liaison with isO, also take part in the work. sO collaborates. closely with the International Etectrotechnical Commission (lEC)on all matters of electrotechnical standardization. Draft international Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Interna- tional Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard Iso 9487 was prepared by Technical Committee ISO/Tc 146, Air quality, Sub-Committee SC 2, Workplace atmospheres. Annexes A, B and C form an integral part of this International Standard. AnnexDisforinformationonly @ ISO 1991 or by any means, electronic or mechanical, including photocopylng and microfilm, without permisslon in writing from the publisher. International Organization for Standardization Case Postale 56 · CH-1211 Geneve 20 · Switzerland Printed in Swltzerland ii Not for Resale d without license from IHS ISO 9487:1991(E) INTERNATIONAL STANDARD Workplace air - Determination of vaporous aromatic hydrocarbons -- Charcoal tube/solvent desorption/gas chromatographic method The method is valid for concentrations of airborne Scope 7 vapours of these compounds in the range from ap- proximately 1 mg/m3 to 1000 mg/m3 (about 0,2 ml/m3 to 200 ml/m3: see 8.1). when sampling 10 litres of air. This International Standard specifies a charcoal NOTE 1 The upper limit of the useful range is set by the tube/gas .chromatographic method for the determi- adsorptive capacity of the first section of the charcoal nation of the concentration of vaporous aromatic tube (5.1) used. This capacity is measured as a break- hydrocarbons in workplace air. through volume of air, which should not be exceeded during sampling (see clause 6 and annex A). The method is valid for the measurement of the The lower limit is set by a number of parameters, includ- concentrations of airborne vapours of any of the fol- ing the noise level of the detector (5.9), blank concen- lowing compounds: trations due to the contamination of the charcoal and carbon disulfide by. the substance analysed, desorption a) benzene: efficiency (see 'annex B) and interference of the soivent peak in the gas chromatographic analysis. b) toluene: The method is also valld for the measurement of c) ethylbenzene: airborne concentrations of mixtures of these com- pounds, In'such cases, the unique properties of each d) m-xylene; compound have to be considered when determining the volume of air to be sampled and the gas chro. e) o-xylene; matographic conditions to be used. The method may. be applicable for other substituted monocyclic f)p-xylene; aromatic hydrocarbons, but. its . validity has to be tested. g) styrene (vinylbenzene); NOTE 2 When analysing aromatic hydrocarbon mix- h) cumene (isopropylbenzene): tures with very large differences in concentrations and in which several compounds are present, the reproducibility. i)1,2,3-trimethylbenzene; and repeatability of the compounds of minor importance might be influenced. ) 1,2,4-trimethylbenzene; The method has been val