SIST ISO 19087:2019

INTERNATIONAL ISO
STANDARD 19087
First edition
2018-07
Workplace air — Analysis of
respirable crystalline silica by Fourier-
Transform Infrared spectroscopy
Air des lieux de travail — Mesure de la fraction alvéolaire de la silice
cristalline par spectrométrie infrarouge
Reference number
©
ISO 2018
© ISO 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative reference . 1
3 Terms and definitions . 1
4 Principle . 2
5 Apparatus, equipment and reagents . 3
6 Sampling . 7
6.1 Sample collection . 7
6.2 Transport . 8
7 Preparation . 9
7.1 Preparation of calibration samples . 9
7.1.1 Preparation of direct-on-filter calibration samples . . 9
7.1.2 Preparation of redeposition calibration samples .10
7.1.3 Preparation of KBr pellet calibration samples .10
7.2 Preparation of the collection substrate for indirect analysis .11
7.2.1 PVC, MCE and polycarbonate filters .11
7.2.2 Cellulose nitrate filters .12
7.2.3 Polyurethane foams . .12
7.3 Redeposition onto analysis filter .13
7.3.1 Crucibles from the furnace .13
7.3.2 Bottles or beakers from a plasma asher .13
7.4 Preparation of KBr pellets .14
8 Analytical procedure .14
8.1 Gravimetric analysis for respirable dust .14
8.2 Fourier-Transform Infrared analysis .15
8.2.1 Background correction .15
8.2.2 Measurement .15
8.3 Calibration .15
9 Evaluation of Fourier-Transform Infrared spectra .17
9.1 General aspects .17
9.2 RCS quantification using peak height .17
9.3 RCS quantification using peak integral .18
[12][14]
9.3.1 Determination of the absorption in the range of the analytical bands .18
[20]
9.3.2 Subtraction of a reference spectrum .18
9.3.3 Other evaluation methods .20
9.4 Interferences .20
10 Calculation of results .20
10.1 Concentration of RCS .20
11 Performance characteristics .21
11.1 Limit of detection .21
11.2 Limits of quantification .21
11.3 Uncertainty .21
11.4 Differences between samplers .21
12 Test report .22
Annex A (normative) Sample treatment strategies for the removal of interferences .23
Annex B (informative) Differences between samplers (cyclones and other types) .24
Annex C (informative) .26
Annex D (normative) Examples of dust collection substrates and analysis filters .28
Bibliography .29
iv © ISO 2018 – All rights reserved

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, 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.
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
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 146, Air quality, Subcommittee SC 2,
Workplace air.
Introduction
Respirable crystalline silica (RCS) is a hazard to the health of workers in many industries through
exposure by inhalation. Industrial hygienists and other public health professionals need to determine
the effectiveness of measures taken to control workers’ exposure. The collection of samples of air
during a work activity and then measuring the amount of respirable crystalline silica are often done to
assess an individual’s exposure, their respiratory protection, or the effectiveness of controls. Fourier-
Transform Infrared (FTIR) analysis of crystalline silica in a sample of respirable dust collected on a
collection substrate is employed in many countries to measure and estimate exposure to RCS. FTIR is
able to measure quartz and cristobalite.
This document specifies the analysis procedures for the measurement of RCS through three methods:
a) Direct-on-filter method: a method of analysing RCS directly on the air sample filter. A specific
requirement of this method is that the sampler used for the workplace measurements is the same
as that used for the preparation of calibration samples.
b) Indirect method by redeposition: a method whereby the dust is recovered from the collection
substrate and deposited onto a filter for analysis.
c) Indirect method by potassium bromide (KBr) pellet: a method whereby the dust is recovered from
the collection substrate and pressed into a potassium bromide (KBr) pellet for analysis.
Many different types of sampling apparatus are used to collect respirable dust, according to the
occupational hygiene convention. This document is designed to accommodate the variety of samplers
and collection substrates available to analysts. This document is used in conjunction with ISO 24095
which promotes best practice for these analyses.
vi © ISO 2018 – All rights reserved

INTERNATIONAL STANDARD ISO 19087:2018(E)
Workplace air — Analysis of respirable crystalline silica by
Fourier-Transform Infrared spectroscopy
1 Scope
This document is a standard for the analysis by Fourier-Transform Infrared (FTIR) of respirable
crystalline silica (RCS) in samples of air collected on collection substrates (i.e. filters
...