IEC 60721-3-4:2019
(Main)Classification of environmental conditions - Part 3-4: Classification of groups of environmental parameters and their severities - Stationary use at non-weatherprotected locations
Classification of environmental conditions - Part 3-4: Classification of groups of environmental parameters and their severities - Stationary use at non-weatherprotected locations
IEC 60721-3-4:2019 classifies groups of environmental parameters and their severities to which products are subjected when installed for stationary use at non-weatherprotected locations. Weatherprotected locations where products can be mounted for stationary use permanently or temporarily are addressed in IEC 60721-3-3.
This third edition cancels and replaces the second edition published in 1995 and Amendment 1:1996. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Clause 1: reworded.
b) Clause 2: normative references have been updated.
c) Clause 3: definitions have been updated.
d) Clause 4: reworded and simplified.
e) Clause 5: revised and updated. Several classes have been replaced by completely new classes based on the use of new information obtained from referenced technical reports.
f) Defined values of chemically active substances are now by reference to ISO 9223.
g) Tables 1 through 5: updated.
The contents of the corrigendum of July 2023 have been included in this copy.
Classification des conditions d'environnement - Partie 3-4: Classification des groupements des agents d'environnement et de leurs sévérités - Utilisation à poste fixe, non protégé contre les intempéries
L’IEC 60721-3-4:2019 classifie les groupements d’agents d’environnement et leurs sévérités, auxquels sont soumis des produits montés pour une utilisation à poste fixe dans des emplacements non protégés contre les intempéries. Les emplacements protégés contre les intempéries où peuvent être montés les produits pour une utilisation fixe de manière permanente ou temporaire sont traités dans l’IEC 60721-3-3.
Cette troisième édition annule et remplace la deuxième édition parue en 1995, ainsi que son amendement 1:1996. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) Article 1: reformulation.
b) Article 2: mise à jour des références normatives.
c) Article 3: mise à jour des définitions.
d) Article 4: reformulation et simplification.
e) Article 5: révision et mise à jour. Plusieurs catégories ont été remplacées par des catégories totalement nouvelles fondées sur l’utilisation de nouvelles informations obtenues dans les rapports techniques cités en référence;
f) Les valeurs définies des substances chimiquement actives font désormais référence à l’ISO 9223.
g) Tableaux 1 à 5: mise à jour.
Le contenu du corrigendum de juillet 2023 a été pris en considération dans cet exemplaire.
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IEC 60721-3-4 ®
Edition 3.0 2019-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –
Part 3-4: Classification of groups of environmental parameters and their
severities – Stationary use at non-weatherprotected locations
Classification des conditions d'environnement –
Partie 3-4: Classification des groupements des agents d'environnement et de
leurs sévérités – Utilisation à poste fixe, non protégé contre les intempéries
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IEC 60721-3-4 ®
Edition 3.0 2019-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –
Part 3-4: Classification of groups of environmental parameters and their
severities – Stationary use at non-weatherprotected locations
Classification des conditions d'environnement –
Partie 3-4: Classification des groupements des agents d'environnement et de
leurs sévérités – Utilisation à poste fixe, non protégé contre les intempéries
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 19.040 ISBN 978-2-8322-6956-5
– 2 – IEC 60721-3-4:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 General . 6
5 Classification of groups of environmental parameters and their severities . 7
5.1 General . 7
5.2 Climatic conditions (K) . 7
5.3 Special climatic conditions (Z). 8
5.4 Biological conditions (B) . 8
5.5 Chemically active substances (C) . 8
5.6 Mechanically active substances (S) . 8
5.7 Mechanical conditions (M) . 8
(informative) Interdependence of air temperature, relative air humidity, and
absolute air humidity . 12
(informative) Definition of seismic environment . 13
Bibliography . 15
Figure A.1 – Climatogram of interdependence of air temperature, relative air humidity,
and absolute air humidity . 12
Table 1 – Classification of climatic conditions . 9
Table 2 – Classification of special climatic conditions . 10
Table 3 – Classification of biological conditions . 10
Table 4 – Classification of mechanically active substances . 10
Table 5 – Classification of mechanical conditions . 11
Table B.1 – Correlation of seismic zones with expected magnitudes . 14
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CLASSIFICATION OF ENVIRONMENTAL CONDITIONS –
Part 3-4: Classification of groups of environmental parameters and
their severities – Stationary use at non-weatherprotected locations
FOREWORD
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International Standard IEC 60721-3-4 has been prepared by IEC technical committee 104:
Environmental conditions, classification, and methods of test.
This third edition cancels and replaces the second edition published in 1995 and
Amendment 1:1996. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Clause 1: reworded.
b) Clause 2: normative references have been updated.
c) Clause 3: definitions have been updated.
d) Clause 4: reworded and simplified.
– 4 – IEC 60721-3-4:2019 © IEC 2019
e) Clause 5: revised and updated. Several classes have been replaced by completely new
classes based on the use of new information obtained from referenced technical reports.
f) Defined values of chemically active substances are now by reference to ISO 9223.
g) Tables 1 through 5: updated.
The text of this International Standard is based on the following documents:
FDIS Report on voting
104/828/FDIS 104/836/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60721 series, published under the general title Classification of
environmental conditions, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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