EN IEC 60721-3-4:2019

SLOVENSKI STANDARD
01-oktober-2019
Nadomešča:
SIST EN 60721-3-4:2001
SIST EN 60721-3-4:2001/A1:2002
Klasifikacija okoljskih pogojev - 3-4. del: Klasifikacija skupin okoljskih parametrov
in njihove resnosti - Stacionarna uporaba na lokacijah, ki niso zaščitene pred
vremenskimi vplivi (IEC 60721-3-4:2019)
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)
Klassifizierung von Umweltbedingungen - Teil 3-4: Klassen von Umwelteinflußgrößen
und deren Grenzwerte - Ortsfester Einsatz, nicht wettergeschützt (IEC 60721-3-4:2019)
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 (IEC 60721-3-4:2019)
Ta slovenski standard je istoveten z: EN IEC 60721-3-4:2019
ICS:
19.040 Preskušanje v zvezi z Environmental testing
okoljem
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60721-3-4

NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2019
ICS 19.040 Supersedes EN 60721-3-4:1995 and all of its
amendments and corrigenda (if any)
English Version
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)
Classification des conditions d'environnement - Partie 3-4: Klassifizierung von Umgebungsbedingungen - Teil 3-4:
Classification des groupements des agents Klassen von Einflussgrößen und deren Grenzwerte –
d'environnement et de leurs sévérités - Utilisation à poste Ortsfester Einsatz, nicht wettergeschützt
fixe, non protégé contre les intempéries (IEC 60721-3-4:2019)
(IEC 60721-3-4:2019)
This European Standard was approved by CENELEC on 2019-06-26. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60721-3-4:2019 E

European foreword
The text of document 104/828/FDIS, future edition 3 of IEC 60721-3-4, prepared by IEC/TC 104 "Environmental
conditions, classification and methods of test" was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN IEC 60721-3-4:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national level by (dop) 2020-03-26
publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-06-26
document have to be withdrawn
This document supersedes EN 60721-3-4:1995 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CENELEC shall not be held responsible for identifying any or all such patent rights.

Endorsement notice
The text of the International Standard IEC 60721-3-4:2019 was approved by CENELEC as a European
Standard without any modification.

In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60068-2-27 NOTE Harmonized as EN 60068-2-27
IEC 60068-3-3 NOTE Harmonized as EN 60068-3-3
IEC 60721-2 (series) NOTE Harmonized as EN 60721-2 (series)
IEC 60721-1 NOTE Harmonized as EN 60721-1
IEC 60721-2-1 NOTE Harmonized as EN 60721-2-1
IEC 60721-2-2 NOTE Harmonized as EN 60721-2-2
IEC 60721-2-3 NOTE Harmonized as EN 60721-2-3
IEC 60721-2-4 NOTE Harmonized as EN IEC 60721-2-4
IEC 60721-2-5 NOTE Harmonized as HD 478.2.5 S1
IEC 60721-2-6:1990 NOTE Harmonized as HD 478.2.6 S1:1993 (not modified)
IEC 60721-2-9 NOTE Harmonized as EN 60721-2-9
IEC 60721-3 (series) NOTE Harmonized as EN 60721-3-9 (series)
IEC 60721-3-0 NOTE Harmonized as EN 60721-3-0
IEC 60721-3-3 NOTE Harmonized as EN 60721-3-3
ISO 9223 NOTE Harmonized as EN ISO 9223

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

IEC 60721-3-4:2019 © IEC 2019 – 3 –
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
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
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/
...