prEN ISO 23861

Workplace air - Chemical agent present as a mixture of airborne particles and vapours - Requirements for evaluation of measuring procedures using samplers (ISO/DIS 23861:2021)

This document specifies performance requirements and test methods under prescribed laboratory conditions for the evaluation of pumped samplers used in conjunction with an air sampling pump and of procedures using these samplers for the determination of semi-volatile chemical agent in workplace atmospheres. The procedures given in this document provide results only for the sum of airborne particles and vapour. The concentration is calculated in terms of mass per unit volume. This document is applicable to pumped samplers and measuring procedures using these samplers in which sampling and analysis are carried out in separate stages.

Luft am Arbeitsplatz - Chemischer Arbeitsstoff, der als Gemisch aus luftgetragenen Partikeln und Dampf vorliegt - Anforderungen an die Bewertung von Messverfahren mit gepumpten Proben (ISO/DIS 23861:2021)

Air des lieux de travail - Agent chimique présent sous forme de mélange de particules en suspension dans l’air et de vapeurs - Exigences d’évaluation des procédures de mesure utilisant des dispositifs de prélèvement (ISO/DIS 23861:2021)

Zrak na delovnem mestu - Kemični agensi, prisotni kot zmesi lebdečih delcev in par - Zahteve za vrednotenje merilnih postopkov z vzorčevalniki (ISO/DIS 23861:2021)

General Information

• Status: Not Published
• ICS: 13.040.30 - Workplace atmospheres
• Technical Committee: CEN/TC 137 - Assessment of workplace exposure
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Due Date: 19-May-2022
• Completion Date: 19-May-2022
• Ref Project: oSIST prEN ISO 23861:2021 - Workplace air - Chemical agent present as a mixture of airborne particles and vapours - Requirements for evaluation of measuring procedures using samplers (ISO/DIS 23861:2021)

RELATIONS

• Revised: EN 13936:2014 - Workplace exposure - Procedures for measuring a chemical agent present as a mixture of airborne particles and vapour - Requirements and test methods
• Effective Date: 14-Oct-2020

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 23861:2021
01-oktober-2021
Zrak na delovnem mestu - Kemični agensi, prisotni kot zmesi lebdečih delcev in
par - Zahteve za vrednotenje merilnih postopkov z vzorčevalniki (ISO/DIS
23861:2021)

Workplace air - Chemical agent present as a mixture of airborne particles and vapours -

Requirements for evaluation of measuring procedures using samplers (ISO/DIS
23861:2021)

Luft am Arbeitsplatz - Chemischer Arbeitsstoff, der als Gemisch aus luftgetragenen

Partikeln und Dampf vorliegt - Anforderungen an die Bewertung von Messverfahren mit

gepumpten Proben (ISO/DIS 23861:2021)

Air des lieux de travail - Agent chimique présent sous forme de mélange de particules en

suspension dans l’air et de vapeurs - Exigences d’évaluation des procédures de mesure

utilisant des dispositifs de prélèvement (ISO/DIS 23861:2021)
Ta slovenski standard je istoveten z: prEN ISO 23861
ICS:
13.040.30 Kakovost zraka na delovnem Workplace atmospheres
mestu
oSIST prEN ISO 23861:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 23861:2021
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oSIST prEN ISO 23861:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 23861
ISO/TC 146/SC 2 Secretariat: ANSI
Voting begins on: Voting terminates on:
2021-08-24 2021-11-16
Workplace air — Chemical agent present as a mixture
of airborne particles and vapours — Requirements for
evaluation of measuring procedures using samplers
ICS: 13.040.30
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 23861:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021
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oSIST prEN ISO 23861:2021
ISO/DIS 23861:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021

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
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Published in Switzerland
ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 23861:2021
ISO/DIS 23861:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Symbols and abbreviated terms ........................................................................................................................................................... 2

5 Sampler types .......................................................................................................................................................................................................... 2

6 Requirements .......................................................................................................................................................................................................... 2

6.1 General ........................................................................................................................................................................................................... 2

6.2 Sampler requirements ...................................................................................................................................................................... 3

6.2.1 General...................................................................................................................................................................................... 3

6.2.2 Flow resistance and stability of the air flow ............................................................................................ 3

6.2.3 Connecting parts .............................................................................................................................................................. 3

6.2.4 Pumps ........................................................................................................................................................................................ 3

6.3 Measuring procedure requirements .................................................................................................................................... 3

6.3.1 Sampling procedure requirements .................................................................................................................. 3

6.3.2 Analytical procedure requirements ................................................................................................................ 4

6.3.3 Expanded uncertainty ................................................................................................................................................. 5

6.3.4 Method description ....................................................................................................................................................... 5

7 General test conditions .................................................................................................................................................................................. 5

7.1 Reagents........................................................................................................................................................................................................ 5

7.2 Apparatus .................................................................................................................................................................................................... 5

8 Test methods ............................................................................................................................................................................................................. 6

8.1 Spiking method ....................................................................................................................................................................................... 6

8.1.1 General...................................................................................................................................................................................... 6

8.1.2 Deposit of the analyte on the first collection substrate .................................................................. 6

8.1.3 Deposit of the analyte on the others collections substrates of a type A sampler..... 6

8.1.4 Transfer of the analyte ................................................................................................................................................ 7

8.2 E valuation of measuring procedures ................................................................................................................................... 7

8.2.1 General...................................................................................................................................................................................... 7

8.2.2 Storage after sampling ................................................................................................................................................ 7

8.3 Uncertainty of the measurement ............................................................................................................................................ 8

8.3.1 Calculation of the combined standard uncertainty ........................................................................... 8

8.3.2 Calculation of the expanded uncertainty .................................................................................................... 8

9 Test report ................................................................................................................................................................................................................... 8

Annex A (informative) Physical behaviour of a mixture of airborne particles and vapour ........................9

Annex B (informative) Possible approaches to sample mixtures of airborne particles and

vapour ...........................................................................................................................................................................................................................13

Annex C (informative) Estimation of uncertainty of measurement ..................................................................................16

Bibliography .............................................................................................................................................................................................................................19

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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 of 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 www .iso .org/

iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 146, Air quality, Subcommittee SC 2,

Workplace atmospheres in collaboration with CEN/TC 137, Assessment of workplace exposure to chemical

and biological agents.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved
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Introduction

This document provides a framework for assessing the performance of procedures for measuring a

chemical agent present as a mixture of airborne particles and vapours against the general requirements

for the performance of procedures for measuring chemical agents in workplace atmospheres as

specified in ISO 20581.

This document enables manufacturers and users of samplers and developers and users of procedures

for measuring a chemical agent present as a mixture of airborne particles and vapours to adopt a

consistent approach to method validation.

This document is based on EN 13936:2014, published by the European Committee for Standardization

(CEN).
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oSIST prEN ISO 23861:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 23861:2021(E)
Workplace air — Chemical agent present as a mixture
of airborne particles and vapours — Requirements for
evaluation of measuring procedures using samplers
1 Scope

This document specifies requirements for the evaluation of measuring procedures using samplers for

the determination of a chemical agent present in the workplace atmosphere as a mixture of airborne

particles and vapours.

The procedures given in this document provide results only for the sum of airborne particles and

vapours. The concentration is calculated in terms of mass per unit volume.

NOTE Examples of substances which can be present in multiple phases are toluene diisocyanate,

diethanolamine, ethyleneglycol or tributhylphosphate.

This document can also be applied to complex mixtures, such as metal working fluids or bitumen fumes.

This document is applicable to samplers and measuring procedures using these samplers in which

sampling and analysis are carried out in separate stages.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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 7708:1996, Air quality — Particle size fraction definitions for health-related sampling (eq. EN 481)

ISO 13137:2013, Workplace atmospheres — Pumps for personal sampling of chemical and biological

agents — Requirements and test methods
ISO 18158, Workplace air — Terminology

ISO 20581, Workplace air — General requirements for the performance of procedures for the measurement

of chemical agents

ISO 21832:2018, Workplace air — Metals and metalloids in airborne particles — Requirements for

evaluation of measuring procedures

ISO 22065:2020, Workplace air — Gases and vapours — Requirements for evaluation of measuring

procedures using pumped samplers

EN 13205-1, Workplace exposure — Assessment of sampler performance for measurement of airborne

particle concentrations — Part 1: General requirements
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 18158 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
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3.1
mixed-phase sampler

sampler or sampling train that is used to collect airborne particles and vapours onto one or more

collection substrates

[SOURCE: ISO 18158:2016, 2.2.2.1.7, modified – The given cross-references have been removed.]

3.2
joint extraction mode

procedure that simultaneously extracts and analyses all collection substrates contained in the mixed-

phase sampler, resulting in a unique quantification of the analyte for each air sample

3.3
separate extraction mode

procedure that separately extracts and analyses the collection substrates contained in the mixed-phase

sampler, resulting in multiple quantifications for each air sample that are summed to give the final

result
4 Symbols and abbreviated terms

For the purposes of this document, the following symbols and abbreviations apply.

OELV occupational exposure limit value
5 Sampler types

Samplers are classified based on differences in the collection substrate because of differences in the

analytical procedures.

Where the vapour phase is collected on a sorbent bed the mixed-phase sampler is classified as type A

sampler.

Where the vapour phase is collected on an impregnated filter the mixed-phase sampler is classified as

type B sampler.

NOTE Other systems, for example denuder and filter or impinger and filter, can be used alternatively for

specific chemical agents. See Annex B.
6 Requirements
6.1 General

The measuring procedure used shall comply with the requirements of ISO 20581 and those clauses of

ISO 13137, ISO 21832, ISO 22065 and EN 13205-1 which apply.

Measuring procedures shall meet the requirements specified in 6.3. When use of a sampler for

measurement of a particular mixture of airborne particles and vapours is claimed, the sampler shall

meet the requirements specified in 6.2.

Known or suspected interferences shall be noted as required by 6.3.4. The results of any tests performed

to evaluate interferences, including suitable and sufficient information to minimize their effects shall

be presented in the method description as required by 6.3.4.
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6.2 Sampler requirements
6.2.1 General

The sampler shall comply with the general requirements given in EN 13205-1 and with the performance

requirements for pumped samplers prescribed in ISO 22065:2020, 6.2.2 to 6.2.6.
6.2.2 Flow resistance and stability of the air flow

The back pressure of the mixed-phase sampler shall not exceed the maximum values specified for the

pump performance test in ISO 13137, unless the combination of mixed-phase sampler and pump has

been tested and shown to be able to sample for the required sampling period.

The air flow through the sampling train associated with the pump shall be measured over the duration

of the sampling period and not deviate more than 5 % as specified in ISO 13137.

Pumps used with size-selective mixed-phase samplers shall also meet the pump pulsation test as

specified in ISO 13137.
6.2.3 Connecting parts

The volume of any connecting parts between collection substrates within the mixed-phase sampler

shall be kept to a minimum and any connection shall be made of an inert material that

— does not retain the chemical agent of interest,
— does not react with the chemical agent of interest,
— does not emit chemical agents that can interfere with the one of interest,
— is resistant to solvents, if applicable.
6.2.4 Pumps
Measuring procedures shall specify the use of pumps complying with ISO 13137.
6.3 Measuring procedure requirements
6.3.1 Sampling procedure requirements
6.3.1.1 General

Measuring procedures shall specify the use of a mixed-phase sampler designed to collect the inhalable

fraction of airborne particles, as defined in ISO 7708, and vapours.

The requirements specified in ISO 22065:2020, 6.3.1 shall apply according to the types of collection

substrates that are used in the mixed-phase sampler.

NOTE Due to the particularity of mixed-phase samplers, some requirements are adapted from ISO 22065 as

given in 6.3.1.2 and 6.3.1.3.
6.3.1.2 Air flow rate

For type A samplers, the air flow rate constrained by the particle-size selector of the sampler should not

exceed the maximal air flow rate of the sorbent tube. If not, the air flow should be split to achieve this

requirement.

For type B samplers, the maximum air flow rate to ensure complete sampling according to

ISO 22065:2020, 6.3.1.3.1 shall comply with the air flow rate required by the particle-size selector used.

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6.3.1.3 Storage condition after sampling

When tested in accordance with the procedure prescribed in 8.2.2, the mean analytical recovery after

storage shall not differ by more than 10 % from the value before storage.
6.3.2 Analytical procedure requirements
6.3.2.1 General

The requirements given in ISO 22065:2020, 6.3.2 shall apply according to the types of collection

substrates that are used in the mixed-phase sampler.

NOTE Due to the particularity of mixed-phase samplers, some requirements are adapted from ISO 22065 as

stated in 6.3.2.2 to 6.3.2.5.
6.3.2.2 Extraction of the collection substrates

The extraction procedure shall ensure that all phases are extracted and presented for analysis of total

mass of the analyte(s) of interest.

When collection substrates are extracted and analysed separately, the masses determined on each

collection substrate shall not be interpreted as accurate separation of a particle fraction or vapour

fraction as these fraction were not stabilized during the sampling period and thus, transfer can occur

between collection substrates.

NOTE However, a preponderance of analyte on the portion of the sampler intended for either particulate

or vapour collection can give valuable guidance regarding the environment and the control measures, including

respiratory protection measures, which may need to be implemented. Samplers which consist of a filter and

adsorbent are not able to give an accurate assessment of partition but samplers have been and are being designed

to provide more accurate information.
6.3.2.3 Analytical quantification limit

The quantification limit shall be lower than or equal to the mass of analyte that would be collected for

the minimum air sample volume specified in the measuring procedure at the following concentrations

and calculated by the Formula (1):
()x⋅ρ
m = ⋅⋅Qt (1)
LoQ min
where
is the fraction of LV considered as follow:
— x=01, for substances with long-term limit value
— x=05, for substances with short-term limit value
m is the minimum of mass of analyte that shall be quantified
LoQ
ρ is the limit value considered

N is the number of extractions realized to analyse all collection substrates, control sections

excluded
Q is the recommended air flow rate of the mixed-phase sampler
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6.3.2.4 nalytical recovery

For extraction when tested in accordance with ISO 22065:2020, 8.3.2.2.3, the analytical recovery R

shall be ≥ 75 % with K ≤ 10 % at each loading.

The values given for analytical recovery are targets; lower values may be used provided equivalent

precision is achieved.
6.3.2.5 Blank value

In order to obtain acceptable values for the limit of quantification of the method, the blank values of the

sampling media should be as low as technically possible.

When tested in accordance with ISO 22065:2020, 8.3.2.3, the total of the blank values shall be less than

one-tenth of the mass calculated by Formula (1).

NOTE Higher blank values can be allowed provided the requirement of 6.3.2.3 is met.

Where it is known that a blank value is significant and varies between batches of samplers, it shall be

checked for each batch.
6.3.3 Expanded uncertainty

When tested in accordance with ISO 22065:2020, 8.3, the expanded uncertainty of the measuring

procedure as a whole, including the measurement of airborne particles and vapour, shall comply with

the requirements of ISO 20581. For the uncertainty budget of the airborne particles the numbers given

for inhalable samplers in ISO 21832:2018, C.3.4 can be used.

When fractions are analysed separately, the expanded uncertainty can be calculated according to

Annex C.3.
6.3.4 Method description
ISO 22065:2020, 6.3.4 shall apply.
7 General test conditions
7.1 Reagents
Use only reagents of recognized analytical grade.
7.2 Apparatus

Test equipment as stated in ISO 22065:2020, 7.2.2 to 7.2.7 shall be used except for 7.2.3.

NOTE 1 A dynamic system for generating, pre-mixing and delivering a known concentration of a test

atmosphere that contains known concentrations of vapours and particles of a semi-volatile compound is

technically difficult to obtain compared to a test atmosphere containing only vapours as prescribed in ISO 22065.

The apparatus described ISO 22065:2020, 7.2.3 can be used to generate the test atmospheres of pure air in the

conditions required by the tests.

NOTE 2 Test atmospheres generated at high concentrations tend to bias towards the aerosol phase compared

to lower concentrations that can be observed in the workplace, therefore it is important that the concentrations

in the test atmosphere are relevant to the sampling situations at workplaces.
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8 Test methods
8.1 Spiking method
8.1.1 General

The spiking method allows the deposit of the analyte on the collection substrates under controlled

conditions. Only if no standard atmosphere chamber for mixtures of vapour and aerosols is available

the spiking method described in 8.1.2 shall be used.

Tests prescribed in 8.2 need the analyte to be spiked on the collection substrates. Due to the semi-

volatile characteristic of the analyte, this spiking shall be made as required by 8.1.2 to 8.1.4.

8.1.2 Deposit of the analyte on the first collection substrate
8.1.2.1 Type A samplers

The first collection substrate of an type A sampler is a filter. A deposit of the analyte in the form of a

spot with micropipette or syringe shall be avoided due to the dramatic reduction of the evaporation

surface in comparison with the one presented by the micrometric airborne particles collected on the

surface of the filter during the sampling period. If so, the transfer of the analyte from the filter to the

sorbent bed will not be realistic.

The analyte shall be deposited on the filter by a syringe with a volume of solution that permits to wet

80 % to 90 % of the front surface of the filter. To do so, the analyte can be diluted in a non-interfering

solvent to deliver the appropriate mass of analyte on the collection substrate.

To prevent any loss of the analyte of interest, a volatile solvent should be used that could passively

evaporate within a minute. If this is not possible, the solvent used shall not interfere with the sorbent

bed or the analytical method.
8.1.2.2 Type B samplers

As far as possible, the analyte shall be homogeneously deposited on the impregnated filter to ensure

that the analyte can react with the reagent of impregnation.

The analyte can be diluted in a non-interfering solvent to deliver the appropriate mass of analyte on the

collection substrate.

8.1.3 Deposit of the analyte on the others collections substrates of a type A sampler

During tests regarding the analytical method (see ISO 22065:2020, 8.3.2.1), the analytical recovery

(see ISO 22065:2020, 8.3.2.2), and the verification of sampler capacity (see ISO 22065:2020, 8.3.1.1), the

subsequent collection substrates of type A sampler, which are sorbent beds, require to be spiked.

The spiking of those collection substrates may preferentially be realized by adding a known mass

of analyte corresponding to the required loading of the corresponding test into a small vessel (for

example, empty sampling tube, pipette reservoir), using a micropipette or syringe. The analyte can be

pure or diluted in a solvent (usually the desorption solvent). The vessel shall be heated enough to permit

the rapid volatilisation of the mass of analyte deposited inside, while air is sampled from the vessel

by pumping onto the sampling medium (recommended flow rate and sampling time shall be used).

Check that all the analyte has evaporated after sampling by rinsing the vessel and any connections with

desorption solvent and analysing the rinsate.

In the case where this technique is not suitable with the physical properties of the analyte, the analyte

can be spiked directly in the sorbent bed by a micropipette or syringe and diluting in a non-interfering

solvent, if necessary.
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8.1
...