ISO 20581:2016

INTERNATIONAL ISO
STANDARD 20581
First edition
2016-11-01
Workplace air — General
requirements for the performance of
procedures for the measurement of
chemical agents
Air des lieux de travail — Exigences générales concernant les
performances des procédures de mesure des agents chimiques
Reference number
©
ISO 2016
© ISO 2016, Published in Switzerland
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ii © ISO 2016 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Classification . 2
4.1 General . 2
4.2 Screening measurements of time-weighted average concentration . 2
4.3 Screening measurements of variation of concentration in time and/or space . 2
4.4 Measurements for comparison with occupational exposure limit values . 2
4.5 Periodic measurements . 2
5 Performance requirements . 3
5.1 General . 3
5.2 Screening measurements of time-weighted average concentration . 3
5.3 Screening measurements of variation of concentration in time and/or space . 3
5.4 Measurements for comparison with limit values and periodic measurements . 3
5.4.1 Unambiguity . 3
5.4.2 Selectivity . 3
5.4.3 Averaging time . 4
5.4.4 Measuring range. 4
5.4.5 Expanded uncertainty . 4
5.4.6 Chemical agents where compliant methods are not available . 4
5.5 Composite procedures. 4
5.6 Transport, handling and/or storage . 5
5.7 Environmental conditions . 5
5.8 Description of measuring procedure . 5
5.9 Dimension of result . 5
5.10 Additional requirements . 5
6 Test method . 6
7 Validation report . 7
Annex A (informative) Structure of a method description . 8
Annex B (informative) Calculation of uncertainty of measurement . 9
Bibliography .16
Foreword
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bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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electrotechnical standardization.
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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
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The committee responsible for this document is ISO/TC 146, Air quality, Subcommittee SC 2, Workplace
atmospheres.
iv © ISO 2016 – All rights reserved

Introduction
National laws and regulations require the assessment of the potential exposure of a worker to chemical
agents in workplace atmospheres. One way of assessing such exposure is to measure the concentration of
a chemical agent in the air in the worker’s breathing zone. The procedures used for such measurements
should provide reliable and valid results for the comparison purpose of exposure measurements with
occupational exposure limit values and for the provision of acceptable control strategies.
This document is based on EN 482:2012, amended by Amendment 1:2015, and introduces general
requirements to fulfil the measurement procedures in the process of quantitative exposure assessment.
Specific International Standards and European Standards have been prepared for different types of
measuring procedures and measuring devices. These include standards for airborne particle samplers
[EN 13205 (all parts)], diffusive samplers (ISO 16107 and EN 838), pumped samplers (EN 1076),
short-term detector tubes (ISO 17621), personal sampling pumps (ISO 13137), metals and metalloids
in airborne particles (EN 13890), mixtures of airborne particles and vapour (EN 13936) and direct
reading instruments for toxic gases and vapours [EN 45544 (all parts)]. In these specific standards,
additional requirements have been included for the procedure or device in question, so that the general
requirements of this document are not compromised. Where no specific International and/or European
Standard exists, only the general requirements apply.
Performance requirements given in this document are intended to apply under environmental
conditions present at the workplace. However, because a wide range of environmental conditions is
encountered in practice, this document specifies requirements that have to be fulfilled by measuring
procedures when tested under prescribed laboratory conditions.
It is the user’s responsibility to choose the appropriate procedures or devices that meet the
requirements of this document. One way of doing this is to obtain information or confirmation from the
provider of a procedure or the manufacturer of a device. Type-testing or, more generally, assessment of
the performance of procedures or devices, can be undertaken by the manufacturer, user, testing house
or research and development laboratory, as is most appropriate. A number of existing procedures for
workplace measurements have either been tested over a part of the required minimum measuring
range, but not over the entire range, or have not been tested for all environmental influences and
potential interferences. If these partially validated procedures meet the performance requirements of
this document, they can be used at present. Nevertheless, these procedures should be tested over the
full ranges as soon as is reasonably practicable.
INTERNATIONAL STANDARD ISO 20581:2016(E)
Workplace air — General requirements for the
performance of procedures for the measurement of
chemical agents
1 Scope
This document specifies general performance requirements for procedures for the determination of
the concentration of chemical agents in workplace atmospheres. These requirements apply to all steps
of measuring procedures regardless of the physical form of the chemical agent (gas, vapour, airborne
particles), measuring procedures with separate sampling and analytical methods, and direct-reading
devices.
This document specifies requirements that have to be fulfilled by measuring procedures when tested
under prescribed laboratory conditions due to a wide range of environmental conditions encountered
in practice.
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 78-2, Chemistry — Layouts for standards — Part 2: Methods of chemical analysis
ISO 7708, Air quality — Particle size fraction definitions for health-related sampling
ISO 13137, Workplace atmospheres — Pumps for personal sampling of chemical and biological agents —
Requirements and test methods
ISO 16107, Workplace atmospheres — Protocol for evaluating the performance of diffusive samplers
ISO 17621, Workplace atmospheres — Short term detector tube measurement systems — Requirements
and test methods
EN 838, Workplace exposure — Procedures for measuring gases and vapours using diffusive samplers —
Requirements and test methods
EN 1076, Workplace exposure — Procedures for measuring gases and vapours using pumped samplers —
Requirements and test methods
EN 13205 (all parts), Workplace exposure — Assessment of sampler performance for measurement of
airborne particle concentrations
EN 13890, Workplace exposure — Procedures for measuring metals and metalloids in airborne particles —
Requirements and test methods
EN 13936, Workplace exposure — Procedures for measuring a chemical agent present as a mixture of
airborne particles and vapour — Requirements and test methods
EN 45544 (all parts), Workplace atmospheres — Electrical apparatus used for the direct detection and
direct concentration measurement of toxic gases and vapours
3 Terms and definitions
For the purpose
...