1、BSI Standards PublicationBS ISO 17734-1:2013Determination oforganonitrogen compoundsin air using liquidchromatography and massspectrometryPart 1: Isocyanates using dibutylaminederivativesBS ISO 17734-1:2013 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 17734-
2、1:2013.It supersedes BS ISO 17734-1:2006 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee EH/2/2, Work place atmospheres.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to
3、 include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 77427 0ICS 13.040.30Compliance with a British Standard cannot confer immunity fromlegal obligations.This
4、British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 December 2013.Amendments issued since publicationDate Text affectedBS ISO 17734-1:2013 ISO 2013Determination of organonitrogen compounds in air using liquid chromatography and mass spectrometry Par
5、t 1: Isocyanates using dibutylamine derivativesDtermination des composs organiques azots dans lair par chromatographie liquide et spectromtrie de masse Partie 1: Isocyanates par les drivs de la dibutylamineINTERNATIONAL STANDARDISO17734-1Second edition2013-12-01Reference numberISO 17734-1:2013(E)BS
6、ISO 17734-1:2013ISO 17734-1:2013(E)ii ISO 2013 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2013All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, o
7、r posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copy
8、rightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 17734-1:2013ISO 17734-1:2013(E) ISO 2013 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Principle 14 Reagents and materials . 35 Preparation of standard solutions . 35.1 Reference compounds 3
9、5.2 Di-n-butylamine (DBA) derivatives of isocyanates . 45.3 DBA derivatives of bulk isocyanates . 55.4 DBA derivatives of isocyanates in thermal decomposition products of polyurethane (PUR) or urea-based resins . 65.5 Stability 66 Apparatus . 66.2 Flow meter. . 86.3 Liquid chromatographic system. .
10、86.4 Ultrasonic bath. . 96.5 Evaporator. 97 Air sampling 97.1 Pre-sampling laboratory preparation . 97.2 Pre-sampling field preparations 97.3 Collection of air samples . 107.4 Blanks . 127.5 Raw material 127.6 Shipment of samples . 128 Laboratory sample preparation 128.1 Sample sequence 128.2 Work-u
11、p procedure 129 Instrumental settings .139.1 HPLC program (LC-MS) 139.2 HPLC program LC-chemiluminescent nitrogen detector (LC-CLND) .139.3 Mass spectrometer . 1310 Data handling 1410.1 Identification . 1410.2 Calibration curves . 1410.3 Quantification . 1411 Interferences .1412 Determination of per
12、formance characteristics.1412.1 General 1412.2 Relevant uncertainty contributions and criteria 1512.3 Assessment of performance characteristics (following the detailed approach in Reference 18) 15Annex A (informative) Performance characteristics 24Annex B (informative) Examples .26Annex C (informati
13、ve) Commercially available products 31Bibliography .32BS ISO 17734-1:2013ISO 17734-1:2013(E)ForewordISO (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 o
14、ut 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, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO c
15、ollaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different app
16、roval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of the elements of this document may be the
17、subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any t
18、rade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the
19、Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 146, Air quality, Subcommittee SC 2, Workplace atmospheres.This second edition of ISO 17734-1 cancels and replaces ISO 17734-1:2006, which has been techn
20、ically revised.ISO 17734 consists of the following parts, under the general title Determination of organonitrogen compounds in air using liquid chromatography and mass spectrometry: Part 1: Isocyanates using dibutylamine derivatives Part 2: Amines and aminoisocyanates using dibutylamine and ethyl ch
21、loroformate derivativesiv ISO 2013 All rights reservedBS ISO 17734-1:2013ISO 17734-1:2013(E)IntroductionIsocyanates have been used in industry for about 50 years. They are commercially important chemicals mainly used for the production of polyurethane (PUR). In spite of controls to limit exposures,
22、there are adverse health effects such as asthma, contact dermatitis, and hypersensitivity pneumonitis as consequences of exposure to isocyanates in some industrial sectors.The analytical method for the determination of isocyanates in workplace air must be sensitive due to the high irritation and sen
23、sitization properties of isocyanates. Extremely low occupational exposure limits (OELs) exist in many countries, and concentrations well below the OEL (1,5 m) sampled in the impinger.For an illustration of the sampling procedure, see Figure 3. Calculate the volume drawn through the sampler from the
24、sampling time and the average sampling flow. The total sampling time is limited (about 30 min), unless the reagent solution is refilled during sampling.If sampling is performed for more than 30 min or at temperatures above 25 C, care should be taken that the sampling solution is not evaporated. If s
25、o, the sampling solution needs to be refilled. Sufficient 0,01 M DBA in toluene is added to the impinger bottle.10 ISO 2013 All rights reservedBS ISO 17734-1:2013ISO 17734-1:2013(E)1 3 5 2 4 Key1 The impinger solution is transferred to the impinger flask.2 The airflow is measured and the sampling pu
26、mp is calibrated to 1 l/min.3 Air sampling4 The airflow is measured.5 The impinger solution and the rinsing solution are transferred to a test tube. The filter is either transferred to the impinger solution tube or to an extraction solution tube.Figure 3 Illustration of the sampling procedure7.3.3 S
27、olvent-free samplingTake off the plugs in both ends just prior to the air sampling. Connect an air sampling pump to the filter-holder outlet with a charcoal vapour trap between the sampler and the pump. Perform the air sampling with an airflow of 0,2 lmin1and check the flow rate before and after sam
28、pling. After sampling, disconnect the sampler from the pump, and plug both ends with polypropylene plugs. No field extraction is necessary. Prolonged sampling (8 h) can be performed without any loss of sampling performance. ISO 2013 All rights reserved 11BS ISO 17734-1:2013ISO 17734-1:2013(E)7.3.4 P
29、ost-sampling field preparationsPumps are calibrated before and after sampling so as to compute the mean flow (12.3.2.1).7.4 BlanksFrom every series of samples, there should be an appropriate number, e.g. 3, of field blanks and lab blanks (n = 3). Field blanks are samples that have been handled exact
30、ly like the other samples out in the field, except that no air has been drawn through. Lab blanks will be useful to identify if there is contamination, if it took place in the lab or in the field.7.5 Raw materialFrom each work-site, it is desirable to collect samples of the raw material suspected of
31、 emitting isocyanates during the work operation. If the material is a bulk isocyanate product, it could be useful for qualitative identification of isocyanate species in the air samples. These products are also applicable for the preparation of the reference solutions for the quantification of unkno
32、wn isocyanates (see 5.2 and 5.3).Collecting and subsequent laboratory testing of materials that are known or are suspected of emitting isocyanates is useful for assessing the exposure. The testing can consist of extraction, heating, or other processing of the material, as similar to the original wor
33、k operation as possible.7.6 Shipment of samplesThe test tubes containing the DBA-toluene samples should be shipped in individual plastic cases and preferably kept in an upright position. The sampling solution tubes should be placed well apart from any raw material collected. Regulations for shipping
34、 hazardous (dangerous) materials should be followed as appropriate.8 Laboratory sample preparation8.1 Sample sequenceIn each sample sequence, a number of samples consist of field blanks, lab blanks, chemical blanks, internal standard blanks, and an appropriate number of calibration standards. Intern
35、al standard blanks are reagent solutions from the same batch as the reagent solution used for air sampling spiked with internal standard in the work-up procedure. Chemical blanks are pure toluene with no addition of internal standard in the work-up procedure.8.2 Work-up procedure8.2.1 GeneralFor the
36、 preparation of the calibration standards, aliquots of 10 ml toluene solutions, containing 0,01 moll1DBA, are spiked with the isocyanate-DBA derivatives to concentrations appropriate for the calibration curve (typically five to seven calibration standards in the range of 0 g/sample to 0,5 g/sample).
37、Upon receiving the air samples from the field, add internal standards (deuterium-labelled isocyanate derivatives) to the air samples, to the standard solutions, to the field blanks, and to the internal standard blanks. Place the samples in an ultrasonic bath for 15 min. If the solutions contain filt
38、ers, place the samples in a centrifuge for 10 min (3 000 r/min). Remove the sample solutions from the filters with a pipette into new test tubes. Evaporate the solvent from the samples and the standards. Dissolve the residues in 0,5 ml acetonitrile and place them in an ultrasonic bath for 15 min.12
39、ISO 2013 All rights reservedBS ISO 17734-1:2013ISO 17734-1:2013(E)8.2.2 Solvent-free samplingTo extract the isocyanate-DBA derivatives from the glass fibre filters, a double extraction to an organic solvent is performed. The filters are carefully removed from the denuder and end filter using tweezer
40、s. The filters are then folded and placed in screw-cap test tubes. To the filter, 3 ml 5 mM H2SO4, 3 ml methanol, and 6 ml toluene are added. An internal standard solution, containing deuterium-labelled isocyanate-DBA derivatives, is also added. Prepare the calibration standards in test tubes contai
41、ning the same extraction solutions and internal standards as the extracted air samples. The filter is then shaken for 5 min, sonicated for 10 min in an ultrasonic bath, and then shaken again for 20 min. After centrifugation for 10 min at 3 000 r/min, the toluene solution is separated to a new test t
42、ube. To the tube containing the filter and mixture of methanol and acid, another aliquot of 6 ml toluene is added, and the extraction procedure is repeated. The toluene is separated to the same test tube as the first, giving a toluene solution with a total volume of about 12 ml. Remove the solvent a
43、nd the excess reagent from the samples by evaporation. Dissolve the residues in 0,5 ml acetonitrile and place them in an ultrasonic bath for 15 min.9 Instrumental settings9.1 HPLC program (LC-MS)For simultaneous determination of the DBA derivatives of monoisocyanates and diisocyanates, the following
44、 mobile phase composition can be used: flow rate: 100 lmin1; 0 min to 15 min: linear gradient from 50 % mobile phase B to 90 % mobile phase B; 15 min to 20 min: re-equilibrate at 50 % mobile phase B.If a single or a few derivatives are to be determined, isocratic elution or gradient elution with app
45、ropriate mobile phase composition can be performed.If high molecular weight DBA derivatives (e.g. prepolymers, isocyanate adducts) are to be determined together with DBA monomers, it is necessary to continue with the gradient up to 100 % B and maintain at 100 % B until all analytes are eluted.9.2 HP
46、LC program LC-chemiluminescent nitrogen detector (LC-CLND)For quantifying DBA derivatives in reference solutions prepared in-lab, generally at higher concentrations, the following mobile phase composition can be used: flow rate: 100 lmin1; 0 min to 15 min: linear gradient from 40 % mobile phase D to
47、 100 % mobile phase D; 15 min to 30 min: 100 % mobile phase D; 30 min to 35 min: re-equilibrate at 40 % mobile phase D.Depending on the properties of the analytes in the sample, stronger, weaker, or isocratic elution can be used.9.3 Mass spectrometerSettings of the MS depend greatly on the type of i
48、nstrument that is used. Optimization is normally performed by the introduction of flow at 100 lmin1of mobile phase containing low and high mass aromatic and aliphatic isocyanate derivatives. Optimal settings vary for the analytes and the ions to be monitored. Practical settings are not the optimum f
49、or all of the compounds to be studied.For quantification, selected ions are monitored, e.g. the molecular ion MH+, but other typical ions can be used, such as (DBA)H+(m/z = 130), (DBA)CO+(m/z = 156), MH-129+, and MNa+(see Annex B.4). ISO 2013 All rights reserved 13BS ISO 17734-1:2013ISO 17734-1:2013(E)For LC-MS/MS quantifications, multiple reaction monitoring is performed by monitoring the daughter ion, (DBA)H+, (DBA)CO+, or MH-129+, from the protonated molecular ion MH+.For identification of unknown
