SIST EN IEC 60721-3-7:2026

Classification of environmental conditions - Part 3-7: Classification of groups of environmental parameters and their severities - Portable and non-stationary use (IEC 60721-3-7:2026)

IEC 60721-3-7:2026 classifies the groups of environmental parameters and their severities to which products are subject to during portable and non-stationary use. This includes periods of transfer, down time, maintenance and repair.
The environmental conditions encompassed by these groups include the environmental conditions occurring
- at locations where the product can be placed or used temporarily, and
- during the transfer of products between different locations.
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a) most classes have been replaced by completely new classes based on the use of new information obtained from referenced Technical Reports;
b) Table 1 through to Table 5 have been updated;
c) the content of the five informative annexes has either been incorporated into the main body of the document or deleted.

Klassifizierung von Umgebungsbedingungen - Teil 3-7: Klassen von Einflussgrößen und deren Grenzwerte - Ortsveränderlicher Einsatz (IEC 60721-3-7:2026)

Classification des conditions d'environnement - Partie 3-7: Classification des groupements des agents d'environnement et de leurs sévérités - Utilisation en déplacement (IEC 60721-3-7:2026)

L'IEC 60721-3-7:2026 classifie les groupements des agents d'environnement et leurs sévérités, auxquels sont soumis les produits utilisés en déplacement. Cela comprend les périodes de transfert, d'immobilisation, de maintenance et de réparation.
Les groupes sont soumis aux conditions d'environnement suivantes:
- aux endroits où le produit peut être placé ou utilisé temporairement; et
- pendant le transfert de produits entre différents endroits.
Cette troisième édition annule et remplace la deuxième édition parue en 1995 et l'Amendement 1:1996. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) la plupart des classes ont été remplacées par des classes totalement nouvelles, établies en fonction de l'utilisation de nouvelles informations obtenues dans les Rapports techniques référencés;
b) les Tableau 1 à Tableau 5 ont été mis à jour;
c) le contenu des cinq annexes informatives a été soit incorporé dans le corps principal du document soit supprimé.

Klasifikacija okoljskih pogojev - 3-7. del: Klasifikacija skupin okoljskih parametrov in njihove resnosti - Prenosna in nefiksna uporaba (IEC 60721-3-7:2026)

IEC 60721-3-7:2026 razvršča skupine okoljskih parametrov in njihove resnosti, katerim so izdelki izpostavljeni med prenosno in nepremično uporabo. To vključuje obdobja prenosa, neaktivnosti, vzdrževanja in popravila.
Okoljske razmere, zajete v teh skupinah, vključujejo okoljske razmere, ki se pojavljajo
- na lokacijah, kjer je mogoče izdelek začasno postaviti ali uporabiti, in
- med prenosom izdelkov med različnimi lokacijami.
Ta tretja izdaja preklicuje in nadomešča drugo izdajo, objavljeno leta 1995, in Dopolnilo 1:1996. Ta izdaja predstavlja tehnično revizijo.
Ta izdaja vključuje naslednje pomembne tehnične spremembe v primerjavi s prejšnjo izdajo:
a) večina razredov je bila nadomeščena s popolnoma novimi razredi, ki temeljijo na uporabi novih informacij, pridobljenih iz referenčnih Tehničnih poročil;
b) Tabela 1 do Tabela 5 so bile posodobljene;
c) vsebina petih informativnih prilog je bila bodisi vključena v glavni del dokumenta bodisi izbrisana.

General Information

• Status: Published
• Public Enquiry End Date: 20-Mar-2025
• Publication Date: 06-Apr-2026
• ICS: 19.040 - Environmental testing
• Technical Committee: I09 - Imaginarni 09
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 24-Mar-2026
• Due Date: 29-May-2026
• Completion Date: 07-Apr-2026
• Ref Project: EN IEC 60721-3-7:2026 - Classification of environmental conditions - Part 3-7: Classification of groups of environmental parameters and their severities - Portable and non-stationary use

Relations

• Replaces: SIST EN 60721-3-7:2001 - Classification of environmental conditions -- Part 3: Classification of groups of environmental parameters and their severities -- Section 7: Portable and non-stationary use
• Effective Date: 01-May-2026
• Replaces: SIST EN 60721-3-7:2001/A1:2001 - Classification of environmental conditions -- Part 3: Classification of groups of environmental parameters and their severities -- Section 7: Portable and non-stationary use
• Effective Date: 01-May-2026
• Refers: SIST EN 60721-1:2001 - Classification of environmental conditions -- Part 1: Environmental parameters and their severities
• Effective Date: 03-Mar-2026
• Referred By: SIST EN 61709:2011 - Electric components - Reliability - Reference conditions for failure rates and stress models for conversion
• Effective Date: 24-Mar-2026
• Referred By: SIST EN IEC 61987-1:2025 - Industrial-process measurement and control - Data structures and elements in process equipment catalogues - Part 1: Generic structures for measuring equipment (IEC 61987-1:2024)
• Effective Date: 24-Mar-2026
• Referred By: SIST EN 50617-1:2015 - Railways applications - Basic parameters of train detection systems - Part 1: Track circuits
• Effective Date: 24-Mar-2026
• Referred By: SIST EN 62282-6-200:2017 - Fuel cell technologies - Part 6-200: Micro fuel cell power systems - Performance test methods (IEC 62282-6-200:2016)
• Effective Date: 24-Mar-2026
• Referred By: SIST EN 60770-3:2014 - Transmitters for use in industrial-process control systems - Part 3: Methods for performance evaluation of intelligent transmitters (IEC 60770-3:2014)
• Effective Date: 24-Mar-2026

Overview

IEC/EN prEN IEC 60721-3-7:2025 (part of the IEC 60721 series) provides a standardized classification of environmental conditions specifically for portable and non-stationary use. It defines groups of environmental parameters and their severities for products that are frequently moved, used during transfer, downtime, maintenance or repair, and for both weatherprotected and non-weatherprotected locations (including land‑based and offshore). The document is intended to guide specification of short‑term environmental stresses and selection of appropriate test severities.

Key topics

• Scope and object: Conditions applicable during transfer, temporary placement and non‑fixed operation; excludes accidental incidents (fire, explosion) and micro‑climates.
• Parameter groups: Classification covers six main groups:
  • Climatic conditions (K) and special climatic (Z)
  • Biological conditions (B)
  • Chemically active substances (C)
  • Mechanically active substances (S)
  • Mechanical conditions (M)
• Severity classes and notation: Uses combined class notations (example: 7K13/7B3/7C2/7S6/7M5) to describe a product’s expected environment.
• Tables and figures: Updated Tables 1–6 list climatic, biological, chemical and mechanical classes; figures illustrate vibration and shock profiles.
• Design and testing guidance: Emphasizes difference between short‑term extreme stresses (may cause immediate malfunction) and long‑term stresses (ageing and degradation). Recommends considering combined environmental effects when specifying design and test conditions.

Applications

• Use IEC 60721-3-7 to:
  • Define environmental requirements for portable electronics, field instruments, mobile communication equipment, test gear and marine portable devices.
  • Select appropriate test severities for environmental qualification and type testing.
  • Draft product specifications and procurement documents that require clear environmental class references.
  • Support design choices (materials, seals, mounting, packaging) and test program development to simulate realistic transfer and on‑site exposure.
• Note: These classes indicate short‑term maximum stresses and are not by themselves sufficient for complete lifetime or reliability assessments - combine with IEC 60721‑2 and relevant technical reports when needed.

Who should use this standard

• Product designers and R&D engineers for portable/non‑stationary equipment
• Test engineers and laboratories performing environmental qualification
• Specification writers, procurement and quality teams
• Certification bodies and technical committees dealing with environmental testing

Related standards

• IEC 60721‑1 (environmental parameters and severities) and other parts of the IEC 60721 series
• IEC technical reports referenced for environmental data: IEC TR 62130, IEC TR 62131‑2/3/4/5
• Prepared by IEC TC 104 (Environmental conditions, classification and methods of test)

Keywords: IEC 60721-3-7, classification of environmental conditions, portable and non-stationary use, environmental parameters, test severities, climatic conditions, mechanical conditions.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2026
Nadomešča:
SIST EN 60721-3-7:2001
SIST EN 60721-3-7:2001/A1:2001
Klasifikacija okoljskih pogojev - 3-7. del: Klasifikacija skupin okoljskih parametrov
in njihove resnosti - Prenosna in nefiksna uporaba (IEC 60721-3-7:2026)
Classification of environmental conditions - Part 3-7: Classification of groups of
environmental parameters and their severities - Portable and non-stationary use (IEC
60721-3-7:2026)
Klassifizierung von Umgebungsbedingungen - Teil 3-7: Klassen von Einflussgrößen und
deren Grenzwerte - Ortsveränderlicher Einsatz (IEC 60721-3-7:2026)
Classification des conditions d'environnement - Partie 3-7: Classification des
groupements des agents d'environnement et de leurs sévérités - Utilisation en
déplacement (IEC 60721-3-7:2026)
Ta slovenski standard je istoveten z: EN IEC 60721-3-7:2026
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 60721-3-7

NORME EUROPÉENNE
EUROPÄISCHE NORM March 2026
ICS 19.040 Supersedes EN 60721-3-7:1995; EN 60721-3-
7:1995/A1:1997
English Version
Classification of environmental conditions - Part 3-7:
Classification of groups of environmental parameters and their
severities - Portable and non-stationary use
(IEC 60721-3-7:2026)
Classification des conditions d'environnement - Partie 3-7: Klassifizierung von Umgebungsbedingungen - Teil 3-7:
Classification des groupements des agents Klassen von Einflussgrößen und deren Grenzwerte -
d'environnement et de leurs sévérités - Utilisation en Ortsveränderlicher Einsatz
déplacement (IEC 60721-3-7:2026)
(IEC 60721-3-7:2026)
This European Standard was approved by CENELEC on 2026-03-13. 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,
Türkiye 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
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60721-3-7:2026 E

European foreword
The text of document 104/1139/FDIS, future edition 3 of IEC 60721-3-7, prepared by TC 104
"Environmental conditions, classification and methods of test" was submitted to the IEC-CENELEC
parallel vote and approved by CENELEC as EN IEC 60721-3-7:2026.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2027-03-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2029-03-31
document have to be withdrawn
This document supersedes EN 60721-3-7:1995 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.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 60721-3-7:2026 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 standard indicated:
IEC 60721-2-1 NOTE Approved as EN 60721-2-1
IEC 60721-2-2 NOTE Approved as EN IEC 60721-2-2
IEC 60721-2-3 NOTE Approved as EN 60721-2-3
IEC 60721-2-4 NOTE Approved as EN IEC 60721-2-4
IEC 60721-2-5 NOTE Approved as HD 478.2.5 S1
IEC 60721-3-0 NOTE Approved as EN IEC 60721-3-0
ISO 9223 NOTE Approved as EN ISO 9223
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 60721-1 - Classification of environmental conditions - EN 60721-1 -
Part 1: Environmental parameters and their
severities
IEC 60721-3-7 ®
Edition 3.0 2026-02
INTERNATIONAL
STANDARD
Classification of environmental conditions -
Part 3-7: Classification of groups of environmental parameters and their
severities - Portable and non-stationary use
ICS 19.040  ISBN 978-2-8327-1038-8

IEC 60721-3-7:2026-02(en)
IEC 60721-3-7:2026 © IEC 2026
CONTENTS
FOREWORD . 2
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 General . 5
5 Classification of groups of environmental parameters and their severities . 6
5.1 General . 6
5.2 Climatic conditions (K) . 6
5.3 Special climatic conditions (Z) . 10
5.4 Biological conditions (B) . 10
5.5 Chemically active substances (C) . 11
5.6 Mechanically active substances (S) . 12
5.7 Mechanical conditions (M) . 13
Bibliography . 16

Figure 1 – Stationary vibration, sinusoidal . 14
Figure 2 – Stationary vibration, random . 15
Figure 3 – Non-stationary shock conditions . 15

Table 1 – Classification of climatic conditions . 8
Table 2 – Classification of special climatic conditions . 10
Table 3 – Classification of biological conditions . 11
Table 4 – Classification of chemically active substances. 12
Table 5 – Classification of mechanically active substances . 13
Table 6 – Classification of mechanical conditions . 13

IEC 60721-3-7:2026 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Classification of environmental conditions -
Part 3-7: Classification of groups of environmental parameters
and their severities - Portable and non-stationary use

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 this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60721-3-7 has been prepared by IEC technical committee 104: Environmental conditions,
classification and methods of test. It is an International Standard.
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) most classes have been replaced by completely new classes based on the use of new
information obtained from referenced Technical Reports;
b) Table 1 through to Table 5 have been updated;
c) the content of the five informative annexes has either been incorporated into the main body
of the document or deleted.
IEC 60721-3-7:2026 © IEC 2026
The text of this International Standard is based on the following documents:
Draft Report on voting
104/1139/FDIS 104/1155/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 60721-3-7:2026 © IEC 2026
1 Scope
This part of IEC 60721 classifies the groups of environmental parameters and their severities
to which products are subject to during portable and non-stationary use. This includes periods
of transfer, down time, maintenance and repair.
The environmental conditions encompassed by these groups include the environmental
conditions occurring
– at locations where the product can be placed or used temporarily, and
– during the transfer of products between different locations.
The conditions of portable and non-stationary use to which products can be exposed include
land-based and offshore, weatherprotected, and non-weatherprotected locations. The
conditions also include those occurring during transfer between locations.
The environmental conditions specified in this document are applicable to products which are
frequently moved from place to place, particularly when the transfer time can be a significant
proportion of the product’s lifetime. During such transfer, the product is unlikely to have any
special packaging.
The environmental conditions specified in this document do not consider the use profile of the
product, i.e., whether the product is used only during a temporary stationary state, during the
state of transfer or arbitrary.
Accidental incidents such as fire, explosion and other unforeseen incidents are not included.
However, it can be important to take their occurrence into account in special cases.
Micro-climates occurring within a product are not included.
Classification for stationary use, storage and transportation environmental conditions are given
in other subparts of the IEC 60721-3 series.
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.
IEC 60721-1, Classification of environmental conditions - Part 1: Environmental parameters and
their severities
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60721-1 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
IEC 60721-3-7:2026 © IEC 2026
3.1
portable and non-stationary use
not permanently mounted on any one structure or placed at a fixed site and which may be
operated either when stationary or been transferred between locations
3.2
weatherprotected
protected from the influences of meteorological conditions
3.3
non-weatherprotected
not protected from the influences of meteorological conditions
4 General
A product can be subjected to a range of environmental conditions during its lifetime. These
conditions have been separated into classes described in IEC 60721-3-0. The classes given
can be used for defining the maximum short-term environmental stresses on a product.
However, they do not provide information regarding the long-term or total lifetime environmental
stresses a product can experience. This means that no reliability or lifetime assessment is
possible based on these classes alone. Refer to IEC 60721-2-1, IEC 60721-2-2, IEC 60721-2-3,
IEC 60721-2-4 and IEC 60721-2-5 and applicable technical reports (IEC TR 62130 as well as
IEC TR 62131-3, IEC TR 62131-4, IEC TR 62131-5 and IEC TR 62131-8) for further
information on actual environmental conditions.
A product can be simultaneously exposed to a number of environmental parameters. For
example, solar radiation and temperature, temperature and humidity, as well as vibration and
temperature change. Combinations of the environmental parameters given can increase the
stress effect on a product. Therefore, combined conditions should be considered in the design
and evaluation of a product.
Products should be designed to survive and operate in different environments. Basically, they
will be affected by environmental influences in two ways:
– by the effects of short-term extreme environmental conditions which can directly cause
malfunction or destroy the product;
– by the effect of long-term subjection to non-extreme environmental stresses which can
slowly degrade the product and finally cause malfunction or destruction of the product.
Short-term extreme environmental conditions can occur at any time in a product's life. A product
can be unaffected by an extreme condition when it is new but fail when it is subjected to the
same condition after being used for a long period of time due to the effect of ageing. The order
in which the environmental conditions are applied can affect the results of an evaluation.
It is important for the product specification, when referring to a certain class in the
IEC 60721-3 series, to define whether the product is required to be capable of operating or only
to survive without permanent damage when being exposed to the conditions described by the
class.
IEC 60721-3-7:2026 © IEC 2026
The environmental classes can be used as a basis for the selection of design and test severities
with respect to the consequence of failure. Information contained in the IEC 60721-3 series can
be used as a means to help establish expected requirements for use, storage, transportation,
etc., and in the development of relevant specifications. The selected severities used for testing
should attempt to produce the effects of the actual environment.
EXAMPLE 1 A high temperature test on a heat dissipating product is designed to simulate the thermal effect of
subjecting a product to conditions of high air temperature, solar radiation and other possible heat sour
...