ISO 16000-41:2023

INTERNATIONAL ISO
STANDARD 16000-41
First edition
2023-08
Indoor air —
Part 41:
Assessment and classification
Air intérieur —
Partie 41: Évaluation et classification
Reference number
© ISO 2023
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General . 2
4.1 Procedure . 2
4.2 Parameters . 3
5 Indoor air quality . 3
6 Quality classes . 3
7 Criteria for the definition of the quality classes . 4
7.1 General . 4
7.2 Main parameters. 4
7.3 Secondary parameters . 5
8 A ss e ss ment pla n .6
8.1 Overview . 6
8.2 Documentation and reports . 7
8.3 Purpose of measurements . 8
8.3.1 Possible reasons . 8
8.3.2 Concretisation of assessment. 8
8.4 Preliminary survey . 8
8.4.1 General . 8
8.4.2 Basic investigation . 9
8.4.3 Local inspections . 9
8.4.4 Conditions for the omission of the measurement of parameters . 10
8.5 Investigation plan . 10
8.5.1 General . 10
8.5.2 Normative specifications . 10
8.5.3 Determination of sampling points . 11
8.5.4 Utilization of the interior room . 11
8.5.5 Seasonal fluctuations and ventilation . 11
8.5.6 Complementary outside air measurements .12
8.6 Investigation . 12
8.7 Report .12
8.8 Division in quality classes . 12
Annex A (informative) Quality classes for main parameters.14
Annex B (informative) Standards for the preliminary survey and the design of investigation
plans .21
Bibliography .24
iii
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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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 document 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).
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www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 146, Air quality, Subcommittee SC 6,
Indoor air.
A list of all parts in the ISO 16000 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
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iv
Introduction
In our society, privately and professionally, people stay indoors most of the day. Therefore, the quality of
the indoor air is very decisive for the quality of life and health. This especially applies to small children,
sick people and other vulnerable groups of persons.
Numerous scientific studies verify the positive effects of good indoor air on the overall performance
during learning (e.g. in kindergartens and schools) and working. A consequence of improved indoor air
quality can be, for example, reduced sickness rates and absenteeism.
The entitlement to high-quality indoor air does not contradict economical aspects of energy- and cost-
efficiency. Improvements in the quality of indoor air are achievable with simple measures, for example,
change of behaviour patterns.
This document describes a procedure to classify the air quality of indoor spaces using quality classes.
These quality classes enable the allocation of the room air to a high, medium or low quality. The quality
classes are based on criteria for physical, chemical and biological parameters according to the state
of science and research. These criteria can be both concentration values in the room air (e.g. with
formaldehyde) as well as sensory and other findings in the room itself (e.g. with mould). The basis for
classifying a measured value of a parameter in a quality class is the definition of class boundaries for
quality classes A to C by national institutions, using guide values from national guidelines, European
and international publications and trade literature.
The most frequent pollutant sources indoors are human activities (e.g. domestic-, hobby- and cleaning
activities, tobacco smoke), combustion processes as well as building materials, furnishings and interior
design materials. The exception is the radioactive inert gas radon, which mostly originates from the
geological subsoil and enters the interior spaces via leaks in the building envelope.
A variety of substances can emit into the indoor air from the most diverse pollution sources. For
this reason, the single analysis of a source or pollutant cannot be used as a substitute for an overall
assessment of the indoor air. A meaningful assessment of the indoor air is only achievable by an overall
assessment of all pollutant sources and substances.
This document is intended for specialists who deal with the assessment of indoor air in the course
of planning, construction, operation and use of buildings (e.g. indoor-experts, architects, specialist
planners of trades, building owners, building developers and contracting authorities, maintenance
engineers, lessors). Also included are producers and distributors of products, that are installed and/or
operated indoors (e.g. building products), and possible users.
v
INTERNATIONAL STANDARD ISO 16000-41:2023(E)
Indoor air —
Part 41:
Assessment and classification
1 Scope
This document specifies a procedure for the assessment of the indoor air quality that is valid for all
interior rooms in residential and non-residential buildings with natural or mechanical ventilation, in
which people do not only stay temporarily.
This document is applicable to indoor environments as defined in ISO 16000-1.
The assessment of working materials in workrooms or workplaces in buildings, that are subject to
statutory occupational safety specifications, are excluded from this document. In these rooms, only air
constituents that do not originate from working materials can be assessed according to th
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