SIST ISO 17734-1:2015

INTERNATIONAL ISO
STANDARD 17734-1
Second edition
2013-12-01
Determination of organonitrogen
compounds in air using liquid
chromatography and mass
spectrometry —
Part 1:
Isocyanates using dibutylamine
derivatives
Détermination des composés organiques azotés dans l’air par
chromatographie liquide et spectrométrie de masse —
Partie 1: Isocyanates par les dérivés de la dibutylamine
Reference number
©
ISO 2013
© ISO 2013
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Published in Switzerland
ii © ISO 2013 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Principle . 1
4 Reagents and materials . 3
5 Preparation of standard solutions . 3
5.1 Reference compounds . 3
5.2 Di-n-butylamine (DBA) derivatives of isocyanates . 4
5.3 DBA derivatives of bulk isocyanates . 5
5.4 DBA derivatives of isocyanates in thermal decomposition products of polyurethane (PUR)
or urea-based resins . 6
5.5 Stability . 6
6 Apparatus . 6
6.2 Flow meter. . 8
6.3 Liquid chromatographic system. . 8
6.4 Ultrasonic bath. . 9
6.5 Evaporator. . 9
7 Air sampling . 9
7.1 Pre-sampling laboratory preparation . 9
7.2 Pre-sampling field preparations . 9
7.3 Collection of air samples .10
7.4 Blanks . .12
7.5 Raw material .12
7.6 Shipment of samples .12
8 Laboratory sample preparation .12
8.1 Sample sequence .12
8.2 Work-up procedure .12
9 Instrumental settings .13
9.1 HPLC program (LC-MS) .13
9.2 HPLC program [LC-chemiluminescent nitrogen detector (LC-CLND)] .13
9.3 Mass spectrometer .13
10 Data handling .14
10.1 Identification .14
10.2 Calibration curves .14
10.3 Quantification .14
11 Interferences .14
12 Determination of performance characteristics.14
12.1 General .14
12.2 Relevant uncertainty contributions and criteria .15
12.3 Assessment of performance characteristics (following the detailed approach in
Reference [18]) .15
Annex A (informative) Performance characteristics .24
Annex B (informative) Examples .26
Annex C (informative) Commercially available products .31
Bibliography .32
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
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ISO collaborates 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 approval 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 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 trade name used in this document is information given for the convenience of users and does not
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For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The 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
technically 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 chloroformate derivatives
iv © ISO 2013 – All rights reserved

Introduction
Isocyanates 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, 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 sensitization properties of isocyanates. Extremely low occupational exposure
limits (OELs) exist in many countries, and concentrations well below the OEL (< 1/100) are often to be
determined. Isocyanates are very reactive and therefore cannot be analysed directly. Derivatization
during sampling is required in order to prevent interfering reactions. Hundreds of different isocyanates
are used in industry, and many more are formed during thermal degradation of PUR. Therefore, high
selectivity of the analytical method is required for accurate results.
The determination of isocyanates in the work environment using di-n-butylamine (DBA) as a reagent and
liquid chromatography-mass spectrometric detection (LC-MS) has been demonstrated to be a robust
method. The development of the method was initiated when difficulties using the “older” methods during
sampling of isocyanates in complex atmospheres were encountered (e.g. thermal decomposition of PUR).
[1][2][3]
The reaction rate between DBA and isocyanates was found to be fast, and high concentrations
can be used to secure instantaneous reactions and eliminate problems with interfering compounds.
[4][5]
Using impinger flasks containing a reagent solution and a filter in series efficiently collects and
[6]
derivatizes isocyanates in both the gas and the particle phase. LC-MS/MS of the isocyanate-DBA
−6 [7]
derivatives enables highly selective and precise determinations down to levels below 10 of the OEL.
Solvent-free sampling can also be performed by using a tube coated with a DBA-impregnated glass fibre
filter followed by an impregnated filter. An impregnation solution containing DBA together with an acid
...