1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 17736:2010Workplace air quality Determination of isocyanate in air using a double-filter sampling device and analysis by high pressure liquid chromatographyBS ISO 17736:20
2、10 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 17736:2010. The UK participation in its preparation was entrusted to Technical Committee EH/2/2, Work place atmospheres.A list of organizations represented on this committee can be obtained on request to its se
3、cretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. BSI 2011 ISBN 978 0 580 66739 8 ICS 13.040.30 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was
4、 published under the authority of the Standards Policy and Strategy Committee on 31 May 2011.Amendments issued since publicationDate Text affectedBS ISO 17736:2010Reference numberISO 17736:2010(E)ISO 2010INTERNATIONAL STANDARD ISO 17736First edition 2010-12-15Workplace air quality Determination of i
5、socyanate in air using a double-filter sampling device and analysis by high pressure liquid chromatography Qualit de lair des lieux de travail Dosage des isocyanates dans lair au moyen dun dispositif dchantillonnage filtre double et par analyse par chromatographie liquide haute performance BS ISO 17
6、736:2010ISO 17736:2010(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing.
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9、ddress given below. COPYRIGHT PROTECTED DOCUMENT ISO 2010 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either
10、ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 g120 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2010 All rights reservedBS ISO 17736:2010ISO
11、17736:2010(E) ISO 2010 All rights reserved iiiContents Page Foreword .iv Introductionv 1 Scope.1 2 Normative references.1 3 Principle 1 4 Reagents and materials . 2 5 Apparatus3 6 Air sampling4 6.1 Calibration of sampling system 4 6.2 Preparation of sampling equipment.4 6.3 Preparation of MAMA-impre
12、gnated filter . 4 6.4 Collection of samples 4 6.5 Blanks5 7 Procedure5 7.1 Safety precautions .5 7.2 Calibration standard. 5 8 Sample processing. 6 8.1 Vapour analysis 6 8.2 Aerosol analysis .6 9 HPLC conditions.7 9.1 General 7 9.2 HPLC conditions vapour isocyanates . 7 9.3 HPLC conditions aerosol i
13、socyanates . .7 10 Analysis.8 10.1 Calibration curve 8 10.2 Quality control . .8 10.3 Sample quantification . .8 11 Interference .9 12 Determination of performance characteristics . 10 12.1 Introduction.10 12.2 Relevant uncertainty contributions and criteria . 10 12.3 Assessment of performance chara
14、cteristics, following the detailed approach in ISO/IEC Guide 98-35. 11 Annex A (informative) Performance characteristics . .18 Annex B (informative) Sample chromatograms. .20 Bibliography.27 BS ISO 17736:2010ISO 17736:2010(E) iv ISO 2010 All rights reservedForeword ISO (the International Organizatio
15、n 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
16、 the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Inter
17、national Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publicat
18、ion as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent righ
19、ts. ISO 17736 was prepared by Technical Committee ISO/TC 146, Air quality, Subcommittee SC 2, Workplace atmospheres. BS ISO 17736:2010 ISO 17736:2010(E) ISO 2010 All rights reserved vIntroduction Isocyanates are commercially available chemicals used in the polyurethane industry. They are known to ca
20、use health problems, such as asthma, contact dermatitis and hypersensitivity pneumonitis, in workers even at very low levels in occupational environments. Since isocyanates are highly reactive compounds and exposure limits are very low, the sampling and the analysis of these substances are critical.
21、 This method is based on the standard method developed by the Institut de Recherche en Sant et en Scurit du Travail Occupational Health and Safety Research Institute (IRSST) of Quebec. It has been in use for more than 18 years as the standard government method in that province of Canada. Since 1996,
22、 it has been introduced into the marketplace in the USA, Brazil, and the UK. After a years study (Reference 10), the method was adopted in 1998-11 by the US Air Force as an acceptable alternative to NIOSH Method 5521 for monomeric isocyanates (now withdrawn). The method is now routinely used in the
23、Canadian provinces of Alberta, British Columbia, and Ontario, and in the US state of Washington, which has validated the method for TDI. Thirteen laboratories have been schooled in this analytical method, three in Canada, eight in the USA and Mexico, one in Brazil, and one in the UK. This method has
24、 been in use in several countries for many years and 13 laboratories participate in round robin testing on a regular basis in order to maintain their proficiency. The double-filter method has been validated for different applications of isocyanates such as spray-painting (Reference 11) and foam manu
25、facturing. It has also been compared with other established methods and demonstrated equivalent results (Reference 10). Double-filter methods are also available in ASTM D65617and ASTM D65628for HDI, and ASTM D59329for TDI. ISO draws attention to the fact that it is claimed that compliance with this
26、document may involve the use of a patent concerning the double-filter sampling device for isocyanates. BS ISO 17736:2010BS ISO 17736:2010INTERNATIONAL STANDARD ISO 17736:2010(E) ISO 2010 All rights reserved 1Workplace air quality Determination of isocyanate in air using a double-filter sampling devi
27、ce and analysis by high pressure liquid chromatography 1 Scope This International Standard gives general guidelines for the sampling and analysis of airborne isocyanates in workplace air. This International Standard is appropriate for organic compounds containing free isocyanate functional groups an
28、d is specific for the quantification of monomers, polymers and prepolymers, vapours and aerosols. Differential air sampling is performed with a segregating device which can show the physical state of the isocyanates analysed as found in the field. This capacity, however, may show limitations for giv
29、en situations, e.g. when aerosols collected on the first filter contain free monomer that migrates to the second filter and is then quantified as vapour phase isocyanate. The determination of aromatic monomers includes toluene diisocyanate (TDI) and 4,4-diisocyanato-diphenylmethane (MDI). Aliphatic
30、monomers include isophorone diisocyanate (IPDI), 4,4-methylene bis-(cyclohexyl isocyanate) (HMDI) and 1,6-hexamethylene diisocyanate (HDI). Isocyanate oligomers and prepolymers can also be determined using this method. The double-filter method is designed to determine short-term (15 min) exposure co
31、ncentrations of organic isocyanates in a workplace environment by personal monitoring or by fixed location monitoring. However, if the exposure is expected to be in vapour form only, then sampling time can be extended to 8 h. Since the filter is derivatized in the field immediately after sampling, l
32、oss of isocyanate aerosol because of its reaction with other chemicals is negligible except for very fast-reacting isocyanate systems such as foam spraying of MDI in polyurethane applications. The method is suitable for the measurement of airborne organic isocyanates in the NCO equivalent concentrat
33、ion range of 0,01 g/sample to 2,1 g/sample, corresponding to approximately 0,67 g/m3to 140 g/m3for a 15 l sample volume. This range brackets about eight times the current established threshold limit value (TLV) of 5 ppb for monomers set by many national authorities. 2 Normative references The follow
34、ing referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 5725-2, Accuracy (trueness and precision) of measuremen
35、t methods and results Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method EN 1232, Workplace atmospheres Pumps for personal sampling of chemical agents Requirements and test methods 3 Principle A measured volume of air is drawn through a d
36、ouble-filter sampling device in which the first filter made of polytetrafluoroethylene (PTFE) collects the aerosols and then the isocyanate vapour is absorbed on a glass fibre (GF) filter impregnated with 9-(methylaminomethyl)anthracene (MAMA). The isocyanate present as an aerosol is collected on th
37、e PTFE filter and derivatized immediately after sampling, in a 5 ml solution of 1-(2-methoxyphenyl)piperazine (MP), 0,1 mg/ml in toluene. BS ISO 17736:2010 ISO 17736:2010(E) 2 ISO 2010 All rights reservedBoth isocyanate monomer and oligomer urea derivatives solutions are separated using reversed pha
38、se high performance liquid chromatography (HPLC). Vapour monomers are analysed by HPLC using an ultraviolet (UV) and fluorescence (FL) detector. Fluorescence detection is used when concentrations are less than 25 % of the TLV. Monomeric and oligomeric aerosols are analysed by HPLC with a UV detector
39、 for quantification and a diode array detector (DAD) for identification. Quantification of the monomeric aerosols is made by comparison with the relevant isocyanate monomer standard. The total isocyanate-in-air concentration is calculated from the sum of all the isocyanate-derived peaks calculated a
40、s NCO function. In some cases, a bulk sample is used for calibration and results are reported as mass of base per volume. The quantitative detection limits for isocyanate, defined as 10s, where s is the standard deviation obtained from 10 measurements carried out on a standard solution whose concent
41、ration is close to the expected detection limit, has been estimated to be approximately 0,026 g/sample, 0,029 g/sample, and 0,036 g/sample for vapour phase HDI, TDI, and MDI, respectively. The quantitative detection limit for aerosol phase HDI, TDI, and MDI is 0,031 g/sample. NOTE The calculation of
42、 oligomeric isocyanates by this method is expressed as the total NCO function equivalent, utilizing the response factor of the corresponding monomer for the oligomer calculation. 4 Reagents and materials During the analysis, unless otherwise stated, use only reagents of recognized analytical grade a
43、nd distilled or demineralized water or water of equivalent purity. 4.1 Water, HPLC grade or equivalent. 4.2 1-(2-Methoxyphenyl)piperazine (MP) CAS No. 35386-24-4, g3398 % mass fraction. 4.3 9-(Methylaminomethyl)anthracene (MAMA) CAS No. 73356-19-1, g3399 % mass fraction. 4.4 Acetic acid, glacial CAS
44、 No. 64-19-7, HPLC grade. 4.5 Acetic anhydride CAS No. 108-24-7, certified ACS. 4.6 Triethylamine CAS No. 121-44-8, g3398 % mass fraction assay by GC. 4.7 Phosphoric acid CAS No. 7664-38-2, certified ACS. 4.8 Reagent solvents, commonly toluene CAS No. 108-88-3, dimethylformamide CAS No. 68-12-2, and
45、 acetonitrile CAS No. 75-05-8, should be HPLC grade. They shall be free from compounds co-eluting with the substance(s) of interest. To avoid any interference from the solvent, perform quality controls on each different lot of solvent. 4.9 Buffer solution and HPLC mobile phase. 4.9.1 Triethylamine b
46、uffer vapour analysis. In a 1 l volumetric flask, dilute 30 ml triethylamine (4.6) in water, and make up to the mark with water. Adjust the pH of this solution to 3 using phosphoric acid (4.7). Filter the solution under vacuum with a 0,22 m filter. 4.9.2 Sodium acetate buffer aerosol analysis. Weigh
47、 approximately 12,5 g of sodium acetate in 1 l HPLC grade water (4.1). Adjust the pH of this solution to 6 with glacial acetic acid (4.4). Filter the resulting solution under vacuum with a 0,22 m filter. 4.9.3 Mobile phase vapour analysis. A solvent mixture of acetonitrile (4.8) and triethylamine bu
48、ffer (4.9.1). The appropriate proportion of each solvent depends on the isocyanate analysed, see Table 1. 4.9.4 Mobile phase aerosol analysis. A solvent mixture of acetonitrile (4.8) and sodium acetate buffer (4.9.2). The appropriate proportion of each solvent depends on the isocyanate analysed, see
49、 Table 2. BS ISO 17736:2010 ISO 17736:2010(E) ISO 2010 All rights reserved 34.10 Reagent solutions. 4.10.1 Desorption solution vapour analysis. A solvent mixture of 67 % volume fraction of dimethylformamide (4.8) and 33 % volume fraction mobile phase. 4.10.2 Derivatization solution aerosol analysis. Weigh 10 mg MP (4.2) and transfer it to a 100 ml volumetric flask. Dissolve and make up to the mark with toluene (4.8). The final concentration of this MP solution is equiv
