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 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a) most classes have been replaced by completely new classes based on the use of new information obtained from referenced Technical Reports;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.

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

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.

General Information

Status
Published
Publication Date
05-Feb-2026
Drafting Committee
MT 19 - TC 104/MT 19
Current Stage
PPUB - Publication issued
Start Date
06-Feb-2026
Completion Date
06-Mar-2026

Relations

Effective Date
05-Sep-2023
Effective Date
05-Sep-2023

Overview

IEC 60721-3-7:2026 establishes a classification system for environmental conditions and their severities relevant to products intended for portable and non-stationary use. Developed by the International Electrotechnical Commission (IEC), this standard assists manufacturers, designers, and product specifiers in anticipating the environmental stresses encountered when products are moved or used temporarily in varying locations, including during transfer, down time, maintenance, and repair.

This third edition, published in 2026, is a technical revision, replacing earlier versions from 1995 and their amendments. It features updated and newly established environmental classes, reflects the latest technical knowledge from relevant technical reports, and integrates or removes earlier annex content for enhanced clarity and usability.

Key Topics

  • Classification of Environmental Parameters

    • Climatic (temperature, humidity, air pressure)
    • Special climatic (e.g., heat radiation, movement of air, water exposure)
    • Biological (mould, rodents, termites)
    • Chemically active substances (contaminants, salt mist, industrial emissions)
    • Mechanically active substances (dust, sand)
    • Mechanical conditions (vibration, shock, free fall)
  • Portable and Non-Stationary Use

    • Addresses products not permanently installed and frequently moved between locations.
    • Considers environments such as offices, workshops, storage rooms, building sites, and outdoor settings (both weatherprotected and non-weatherprotected).
  • Environmental Severities

    • Defines varying degrees of environmental impacts to allow informed selection of design and test criteria based on expected usage.
  • Combined Stresses

    • Recognizes simultaneous exposure to multiple environmental factors, which may amplify stress on products.
  • Lifecycle Conditions

    • Emphasizes that exposure can occur while stationary, during transfer, or in temporary locations, and that both short-term and cumulative long-term effects are relevant.

Applications

IEC 60721-3-7:2026 is broadly applicable for organizations and professionals involved in the design, manufacturing, specification, and testing of electrical and electronic products intended for portable and non-stationary applications. Key practical uses include:

  • Product Design and Specification

    • Defining durability requirements to withstand portable use, encompassing harsh conditions encountered during moves or field deployment.
    • Selecting appropriate environmental classes for product documentation and engineering specifications.
  • Quality Assurance and Compliance

    • Informing environmental testing regimes for certifying products against expected real-world conditions.
    • Guiding risk assessments for field service and maintenance activities.
  • Use Case Scenarios

    • Equipment used in building maintenance, mobile communications, medical devices in field operations, portable instrumentation, and IT equipment in temporary installations.
  • Operational Planning

    • Determining proper protection levels for products expected to experience frequent transfer or use in diverse environments, aiding in developing packaging, handling, and transport guidelines.

Related Standards

IEC 60721-3-7:2026 is part of the wider IEC 60721 series on environmental classifications. Related standards for environmental testing and classification include:

  • IEC 60721-1: General definitions and explanation of environmental parameters and severities.
  • IEC 60721-2-1/2-2/2-3/2-4/2-5: Define natural environmental conditions, such as temperature, humidity, precipitation, wind, air pressure, solar radiation, dust, and salt mist.
  • IEC 60721-3-0: Introduction to environmental parameter classification for groups and their severities.
  • IEC TR 62130, IEC TR 62131-3/4/5/8: Provide field data, transportation, storage, and handling conditions.
  • ISO 9223: Corrosion of metals and alloys, for additional information on chemically active environments.

IEC 60721-3-7:2026 supports the development of robust, reliable products by ensuring environmental conditions for portable and non-stationary use are rigorously and systematically classified, providing value across a variety of industries and applications.

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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/6/2026

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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/6/2026

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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/6/2026

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Frequently Asked Questions

IEC 60721-3-7:2026 is a standard published by the International Electrotechnical Commission (IEC). Its full title is "Classification of environmental conditions - Part 3-7: Classification of groups of environmental parameters and their severities - Portable and non-stationary use". This standard covers: 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.

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.

IEC 60721-3-7:2026 is classified under the following ICS (International Classification for Standards) categories: 19.040 - Environmental testing. The ICS classification helps identify the subject area and facilitates finding related standards.

IEC 60721-3-7:2026 has the following relationships with other standards: It is inter standard links to IEC 60721-3-7:1995/AMD1:1996, IEC 60721-3-7:1995. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.

IEC 60721-3-7:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.

Standards Content (Sample)


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

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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

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
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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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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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.
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.
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
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.
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 sources dependent
on the application.
EXAMPLE 2 In a mechanical shock test, the product can be subjected to mechanical shocks of simple pulse shapes
(e.g., half-sine), while the actual conditions cannot be described by such simple pulses.
It is recognized that extreme or special environmental conditions can exist which require
consideration of severities that are not addressed by this document.
5 Classification of groups of environmental parameters and their severities
5.1 General
A number of classes for climatic conditions (K), special climatic conditions (Z), biological
conditions (B), chemically active substances (C), mechanically active substances (S), and
mechanical conditions (M) are specified.
This classification allows for a number of possible combinations of environmental conditions
which bear upon products during their cycle. It represents the real situation concerning
world-wide conditions of usage due to local influences. For certain environmental parameters,
it has not yet been possible to specify quantitative severities.
For a given location or product, reference should be made to the total set of classes as defined
in 5.2 through 5.7, for example:
7K13/7Z2/7B2/7C8/7S2/7M5
5.2 Climatic conditions (K)
NOTE The classes defined in IEC 60721-3-7:1987 and IEC 60721-3-7:1995 have been replaced with new classes
as a result of recent efforts at collecting information regarding climatic conditions. Those results are contained in
Technical Reports referenced in this document.
When selecting appropriate classes, attention should be paid to the fact that the climatic
conditions in weatherprotected locations can depend on the open-air (non-weatherprotected)
conditions, especially air temperature and solar radiation, and the type of transportation
enclosure.
_________
This publication has been withdrawn.
The following conditions are specifie
...


IEC 60721-3-7 ®
Edition 3.0 2026-02
NORME
INTERNATIONALE
Classification des conditions d'environnement -
Partie 3-7: Classification des groupements des agents d'environnement et de
leurs sévérités - Utilisation en déplacement
ICS 19.040  ISBN 978-2-8327-1038-8

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SOMMAIRE
AVANT-PROPOS . 2
1 Domaine d'application . 4
2 Références normatives . 4
3 Termes et définitions. 4
4 Généralités . 5
5 Classification des groupements des agents d'environnement et de leurs sévérités . 6
5.1 Généralités . 6
5.2 Conditions climatiques (K) . 6
5.3 Conditions climatiques spéciales (Z) . 10
5.4 Conditions biologiques (B) . 10
5.5 Substances chimiquement actives (C). 11
5.6 Substances mécaniquement actives (S) . 12
5.7 Conditions mécaniques (M) . 13
Bibliographie . 16

Figure 1 – Vibrations stationnaires, sinusoïdales . 14
Figure 2 – Vibrations stationnaires, aléatoires . 15
Figure 3 – Conditions de choc non stationnaires . 15

Tableau 1 – Classification des conditions climatiques. 8
Tableau 2 – Classification des conditions climatiques spéciales . 10
Tableau 3 – Classification des conditions biologiques . 11
Tableau 4 – Classification des substances chimiquement actives . 12
Tableau 5 – Classification des substances mécaniquement actives . 13
Tableau 6 – Classification des conditions mécaniques . 13

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
Classification des conditions d'environnement -
Partie 3-7: Classification des groupements des agents d'environnement
et de leurs sévérités - Utilisation en déplacement

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8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
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L'IEC 60721-3-7 a été établie par le comité d'études 104 de l'IEC: Conditions, classification et
essais d'environnement. Il s'agit d'une Norme internationale.
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.
Le texte de cette Norme internationale est issu des documents suivants:
Projet Rapport de vote
104/1139/FDIS 104/1155/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à son approbation.
La langue employée pour l'élaboration de cette Norme internationale est l'anglais.
Ce document a été rédigé selon les Directives ISO/IEC, Partie 2, il a été développé selon les
Directives ISO/IEC, Partie 1 et les Directives ISO/IEC, Supplément IEC, disponibles sous
www.iec.ch/members_experts/refdocs. Les principaux types de documents développés par
l'IEC sont décrits plus en détail sous www.iec.ch/publications.
Une liste de toutes les parties de la série IEC 60721, publiées sous le titre général Classification
des conditions d'environnement, trouve sur le site web de l'IEC.
Le comité a décidé que le contenu de ce document ne sera pas modifié avant la date de stabilité
indiquée sur le site web de l'IEC sous webstore.iec.ch dans les données relatives au document
recherché. À cette date, le document sera
– reconduit,
– supprimé, ou
– révisé.
1 Domaine d'application
La présente partie de l'IEC 60721 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.
Les conditions d'utilisation en déplacement auxquelles peuvent être exposés les produits
comprennent les endroits à terre et en mer, protégés ou non contre les intempéries. Les
conditions incluent également celles qui se produisent pendant le transfert entre différents
endroits.
Les conditions d'environnement spécifiées dans le présent document s'appliquent aux produits
qui sont fréquemment déplacés d'un endroit à un autre, en particulier lorsque le temps de
transfert peut représenter une proportion significative de la durée de vie du produit. Pendant
ce transfert, il est peu probable que le produit ait un emballage spécial.
Les conditions d'environnement spécifiées dans le présent document ne prennent pas en
compte le profil d'utilisation du produit, c'est-à-dire si le produit est utilisé seulement pendant
une phase temporairement fixe, pendant la phase de transfert ou de manière arbitraire.
Les incidents accidentels tels que les incendies, explosions et autres incidents imprévisibles
ne sont pas inclus. Toutefois, il peut être important de prendre en compte leur occurrence dans
certains cas spéciaux.
Les microclimats qui apparaissent à l'intérieur d'un produit ne sont pas inclus.
La classification des conditions d'environnement pour l'utilisation à poste fixe, le stockage et le
transport est donnée dans d'autres sous-parties de la série IEC 60721-3.
2 Références normatives
Les documents suivants sont cités dans le texte de sorte qu'ils constituent, pour tout ou partie
de leur contenu, des exigences du présent document. Pour les références datées, seule
l'édition citée s'applique. Pour les références non datées, la dernière édition du document de
référence s'applique (y compris les éventuels amendements).
IEC 60721-1, Classification des conditions d'environnement - Partie 1: Agents d'environnement
et leurs sévérités
3 Termes et définitions
Pour les besoins du présent document, les termes et définitions de l'IEC 60721-1 ainsi que les
suivants s'appliquent.
L'ISO et l'IEC tiennent à jour des bases de données terminologiques destinées à être utilisées
en normalisation, consultables aux adresses suivantes:
– IEC Electropedia: disponible à l'adresse https://www.electropedia.org/
– ISO Online browsing platform: disponible à l'adresse https://www.iso.org/obp
3.1
utilisation en déplacement
non monté de façon permanente sur une structure ou placé sur un site fixe, et qui peut être
actionné soit lorsqu'il est stationnaire, soit lorsqu'il est transféré entre différents endroits
3.2
protégé contre les intempéries
protégé contre les influences des conditions météorologiques
3.3
non protégé contre les intempéries
non protégé contre les influences des conditions météorologiques
4 Généralités
Un produit peut être soumis à une grande variété de conditions d'environnement pendant sa
durée de vie. Ces conditions ont été séparées dans différentes classes, décrites dans
l'IEC 60721-3-0. Ces classes peuvent être utilisées pour définir les contraintes d'environnement
maximales à court terme sur un produit. Toutefois, elles ne fournissent pas d'informations sur
les contraintes d'environnement qu'un produit peut subir à long terme ou au cours de sa durée
de vie totale. Cela signifie qu'aucune évaluation de la fiabilité ou de la durée de vie n'est
possible en s'appuyant uniquement sur ces classes. Pour plus d'informations sur les conditions
d'environnement réelles, voir l'IEC 60721-2-1, l'IEC 60721-2-2, l'IEC 60721-2-3,
l'IEC 60721-2-4 et l'IEC 60721-2-5, et les rapports techniques pertinents (l'IEC TR 62130 ainsi
que l'IEC TR 62131-3, l'IEC TR 62131-4, l'IEC TR 62131-5 et l'IEC TR 62131-8).
Un produit peut être exposé simultanément à un certain nombre d'agents d'environnement. Par
exemple, le rayonnement solaire et la température, la température et l'humidité, ainsi que les
vibrations et les variations de température. Lorsqu'ils sont combinés, les agents
d'environnement indiqués peuvent accroître l'effet des contraintes sur un produit. Par
conséquent, il convient de prendre en compte ces conditions combinées lors de la conception
et de l'évaluation d'un produit.
Il convient de concevoir les produits afin qu'ils survivent et fonctionnent dans différents
environnements. Ces produits sont principalement affectés par les influences
environnementales de deux manières:
– par les effets de conditions d'environnement extrêmes à court terme qui peuvent
directement provoquer un dysfonctionnement ou détruire le produit;
– par l'effet d'une exposition à long terme à des contraintes d'environnement non extrêmes
qui peuvent provoquer une lente dégradation du produit et finalement occasionner un
dysfonctionnement ou une destruction du produit.
Des conditions d'environnement extrêmes à court terme peuvent survenir à tout moment du
cycle de vie du produit. Un produit peut ne pas être affecté par une condition extrême lorsqu'il
est neuf, mais peut présenter un dysfonctionnement lorsqu'il est soumis à la même condition
après une longue période d'utilisation en raison de l'effet du vieillissement. L'ordre dans lequel
les conditions d'environnement sont appliquées peut influencer les résultats d'une évaluation.
Il est important dans la spécification du produit, lorsqu'il est fait référence à une certaine classe
de la série IEC 60721-3, de définir si le produit doit être capable de fonctionner ou uniquement
de survivre sans dommages permanents lorsqu'il est exposé aux conditions décrites par la
classe.
Les classes d'environnement peuvent être utilisées comme facteur déterminant pour le choix
des sévérités de conception et d'essai en fonction des conséquences d'une défaillance. Les
informations contenues dans la série IEC 60721-3 peuvent être utilisées pour faciliter la
définition des exigences prévues pour l'utilisation, le stockage, le transport, etc., ainsi que pour
l'élaboration des spécifications pertinentes. Il convient que les sévérités choisies et utilisées
pour les essais s'efforcent de produire les effets de l'environnement réel.
EXEMPLE 1 Un essai à haute température sur un produit dissipant la chaleur est conçu pour simuler l'effet
thermique d'un produit soumis à des conditions de température de l'air élevée, de rayonnement solaire et d'autres
sources de chaleur possibles en fonction de l'application.
EXEMPLE 2 Lors d'un essai de choc mécanique, le produit peut être soumis à des chocs mécaniques de formes
d'impulsions simples (par exemple, semi-sinusoïdales), alors que les conditions réelles ne peuvent pas être décrites
par des impulsions aussi simples.
Il est reconnu qu'il peut exister des conditions d'environnement extrêmes ou spéciales qui
exigent l'examen de sévérités qui ne sont pas traitées dans le présent document.
5 Classification des groupements des agents d'environnement et de leurs
sévérités
5.1 Généralités
Un certain nombre de classes pour les conditions climatiques (K), les conditions climatiques
spéciales (Z), les conditions biologiques (B), les substances chimiquement actives (C), les
substances mécaniquement actives (S) et les conditions mécaniques (M) sont spécifiées.
Cette classification permet d'établir un certain nombre de combinaisons possibles de conditions
d'environnement qui ont une influence sur les produits au cours de leur cycle. Elle représente
la situation réelle pour des conditions universelles d'utilisation dues aux influences locales. Il
n'a pas encore été possible de spécifier des valeurs quantitatives de sévérité pour certains
agents d'environnement.
Pour un produit ou un endroit donné, il convient de se référer à l'ensemble des classes définies
du 5.2 au 5.7, par exemple:
7K13/7Z2/7B2/7C8/7S2/7M5
5.2 Conditions climatiques (K)
NOTE Les classes définies dans l'IEC 60721-3-7:1987 et l'IEC 60721-3-7:1995 ont été remplacées par de
nouvelles classes à la suite des récentes initiatives de collecte d'informations sur les conditions climatiques. Ces
résultats figurent dans les Rapports techniques référencés dans le présent document.
Lors du choix des classes appropriées, il convient de tenir compte du fait que les conditions
climatiques dans les endroits protégés contre les intempéries peuvent dépendre des conditions
de l'air libre (non protégées contre les intempéries), en particulier la température de l'air et le
rayonnement solaire, ainsi que du type d'enceinte de transport.
_________
Cette publication a été supprimée.
Les conditions suivantes sont spécifiées dans le Tableau 1.
7K8 s'applique à l'utilisation dans, et au transfert direct entre, des endroits fermés à
température régulée, mais sans régulation de l'humidité. Le chauffage et le
refroidissement sont utilisés pour maintenir les conditions exigées, en particulier
lorsqu'il existe une différence importante avec le climat à l'air libre. Les conditions de
cette classe peuvent se rencontrer dans des zones d'habitation et de travail normales,
ainsi que pendant le transfert entre celles-ci. Les produits peuvent être soumis à des
mouvements de l'air environnant et à des rayonnements thermiques générés pa
...


IEC 60721-3-7 ®
Edition 3.0 2026-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions -
Part 3-7: Classification of groups of environmental parameters and their
severities - Portable and non-stationary use

Classification des conditions d'environnement -
Partie 3-7: Classification des groupements des agents d'environnement et de
leurs sévérités - Utilisation en déplacement
ICS 19.040  ISBN 978-2-8327-1038-8

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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

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
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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) 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.
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.
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
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.
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 sources dependent
on the application.
EXAMPLE 2 In a mechanical shock test, the product can be subjected to mechanical shocks of simple pulse shapes
(e.g., half-sine), while the actual conditions cannot be described by such simple pulses.
It is recognized that extreme or special environmental conditions can exist which require
consideration of severities that are not addressed by this document.
5 Classification of groups of environmental parameters and their severities
5.1 General
A number of classes for climatic conditions (K), special climatic conditions (Z), biological
conditions (B), chemically active substances (C), mechanically active substances (S), and
mechanical conditions (M) are specified.
This classification allows for a number of possible combinations of environmental conditions
which bear upon products during their cycle. It represents the real situation concerning
world-wide conditions of usage due to local influences. For certain environmental parameters,
it has not yet been possible to specify quantitative severities.
For a given location or product, reference should be made to the total set of classes as defined
in 5.2 through 5.7, for example:
7K13/7Z2/7B2/7C8/7S2/7M5
5.2 Climatic conditions (K)
NOTE The classes defined in IEC 60721-3-7:1987 and IEC 60721-3-7:1995 have been replaced with new classes
as a result of recent efforts at collecting information regarding climatic conditions. Those results are contained in
Technical Reports referenced in this document.
When selecting appropriate classes, attention should be paid to the fact that the climatic
conditions in weatherprotected locations can depend on the open-air (non-weatherprotected)
conditions, especially air temperature and solar radiation, and the type of transportation
enclosure.
_________
This publication has been withdrawn.
The following conditions are specified in Table 1.
7K8 applies to use at, and direct transfer between, temperature-controlled enclosed
locations, but with not humidity control. Heating or cooling is used to maintain the
required conditions, especially when there is a large difference with the open-air
climate. The conditions of this class can be found in, and during transfer between,
normal living and working areas. Products can experience movement of surrounding
air and heat radiation from adjacent sources, condensed water and other forms of
wetting other than rain. The product will not be subject to precipitation and formation
of ice.
7K9 applies to use at, and direct transfer between, enclosed locations having neither
temperature nor humidity control. However, heating can be used to raise low
temperatures, especially when there is a large difference between the conditions of
this class and open-air conditions. The conditions of this class can be found in, and
during transfer between, entrances or staircases of building, garages, cellars, certain
workshops, building in factories and industrial process plant, unattended equipment
stations, certain telecommunication buildings, ordinary storage rooms for frost
resistant products, farm buildings etc. The product can be subject to the formation of
ice.
7K10 applies to use at, and direct transfer between, totally or partly weatherprotected
locations, situated in geographical areas classified as warm temperature, warm dry,
mild warm, extremely warm dry, mild warm dry, warm damp and warm damp equable.
It also applies to non-weatherprotected locations when the open-air environment is
covered by the restricted group open-air climates. Polar climates are excluded.
7K11 applies to use at, and direct transfer between, totally or partly weatherprotected
locations in buildings of any construction situated in geographical areas classified as
cold temperature, warm temperature, warm dry, mild warm dry, extremely warm dry,
warm damp and warm damp equable. The class additionally encompasses use at non-
weatherprotected locations which are directly exposed to the open-air climate covered
by moderate group of open-air climate.
7K12 applies to use at, and direct transfer between, locations situated in geographical areas
with open-air environment covered by the worldwide group of open-air climates. The
class also encompasses totally or partly weatherprotected locations in buildings of any
construction as well as non-weatherprotected locations directly exposed to open-air
climates. This class also encompasses transportation in unpressurized aircraft.
7K13 applies to use at, and direct transfer between, warm damp and warm damp equable
types of open-air climate (tropical damp type of climate, in areas with tropical rain
forests).
7K14 applies to use at, and direct transfer between, warm dry, mild warm dry and extremely
warm dry types of open-air climate (tropical dry type of climate, in areas near the
tropics such as deserts).
Table 1 – Classification of climatic conditions
Class
Environmental parameter Unit
7K8 7K9 7K10 7K11 7K12 7K13 7K14
e
Low air temperature °C –5 –25 –40 –65 +5 –20
+5
e
High air temperature °C +45 +70 +70 +85 +40 +55
+40
°C +5 –5 –25 –40 –65 +5 –20
Rapid change of temperature to  to  to  to  to  to  to
°C +25 +25 +30 +30 +30 +30 +30
a
% 5 5 5 5 4 30 4
Low relative humidity
a
% 85 95 100 100 100 100 100
High relative humidity
a 3
1 1 0,5 0,1 0,003 6 0,9
Low absolute humidity g/m
a 3
25 29 48 62 78 36 27
High absolute humidity g/m
b
kPa 70 70 70 70 70 70 70
Low air pressure
b
kPa 106 106 106 106 106 106 106
High air pressure
Rate of change of air pressure kPa/min Negligible Negligible Negligible Negligible 6 6 6
h 2 g g g
1 090 1 090 1 090 1 090
Solar radiation W/m None None None
f f f f f f f
Heat radiation Not specified
c
f f f f f f f
m/s
Movement of surrounding air
Condensation Not specified Yes Yes Yes Yes Yes Yes Yes
Precipitation (rain, snow, hail, etc.) Not specified No No Yes Yes Yes Yes Yes
Rain intensity mm/min None None 6 6 15 15 15
i f f f f f
m/s None None
Driving rain
Snow load None None None None None None None
kg/m
d
°C None None +5 +5 +5 +5 +5
Low rain temperature
i
f f f f f f f
Not specified
Water from sources other than rain

Formation of ice and frost (incl. freeze-thaw) Not specified No Yes Yes Yes Yes Yes Yes

a
The low and high relative humidity levels are limited by the low and high absolute humidity, so that, for example, for environmental parameters low temperature and low relative
humidity, or high temperature and high relative humidity, the severities given in Table 1 do not occur simultaneously.
b
The value of 70 kPa represents a limit for open-air conditions, normally at an altitude of 3 000 m. In some geographical areas, open-air conditions can occur at higher altitudes.
Conditions in mines are not considered.
c
A cooling system based on non-assisted convection can be disturbed by adverse movement of surrounding air.
d
This rain temperature should be considered together with high air temperature and solar radiation. The cooling effect of the rain should be considered in connection with the
surface temperature of the product.
e
These are air-conditioned locations with a tolerance of ±2 °C on stated temperature value.
f
If applicable, a special value should be selected from Table 2.
g
Thermal effect of solar radiation is included in the temperature.
h
Thermal effect of solar radiation is not included in the temperature.
i
Sources of water other than rain are encompassed by driving rain.

5.3 Special climatic conditions (Z)
A number of special climatic environmental conditions can be appropriate, in certain
circumstances. Recommended values for these special climatic conditions are shown in
Table 2. The special severities can be selected when specific conditions are known to occur,
and using other values can result in equipment overdesign. The severities can occur in any
combination with any of the other climatic conditions of Table 1.
Table 2 – Classification of special climatic conditions
Environmental parameter Class Unit Special condition Z
High air temperature 7Z14 °C +55
a
7Z15 kPa 84
Low air pressure
7Z1 Negligible
Heat radiation such as in the vicinity of heating
7Z2
systems
Heat radiation None
Heat radiation such as in the vicinity of heating
7Z3 systems, commercial ovens, or industrial
furnaces
7Z4 5
7Z5 10
b
Movement of surrounding air m/s
7Z6 30
7Z7 50
7Z8 Negligible
7Z9 Dripping water
7Z10 Spray water
c
Water from sources other than rain None
7Z11 Splashing water
7Z12 Water jets
7Z13 Water waves
a
Corresponds to an altitude of approximately 1 400 m.
b
A cooling system based on non-assisted convection can be disturbed by movement of surrounding air.
c
Underwater conditions are not considered.

5.4 Biological conditions (B)
No quantitative severity has been specified for the following conditions. The specified
parameters of Table 3 are typical but not necessarily complete.
7B1 applies to use or transfer in areas without risks biological attack. This includes
protective measure, for example such as by product design or installation in locations
of such construction that mould growth or attack by animals are not probable.
7B2 applies to use or transfer in areas where mould growth and attacks of animals, except
termites, can occur.
7B3 applies to use or transfer in areas where attacks by termites can additionally occur.
Table 3 – Classification of biological conditions
Class
Environmental
parameter
7B1 7B2 7B3
Flora Presence of mould, fungus, etc.
Negligible Presence of rodents and other animals harmful to products
Fauna
excluding termites including termites

5.5 Chemically active substances (C)
The contamination of the natural atmosphere is mainly caused by chemical emissions from
industrial activities, motor-driven vehicles, and heating systems. A further chemical influence is
caused by aerosols of sea and road salts. Contamination can affect the product’s function and
materials. The parameters shown in Table 4 are estimates based on information available at
the time of publication. It is recommended that reference be made to local or regional
information specific to an area of interest when establishing requirements.
7C5 applies to use at, and direct transfer between, locations with stringently monitored and
controlled atmosphere.
7C6 applies to use at, and direct transfer between, locations with continuously controlled
atmosphere.
7C7 applies to use at, and direct transfer between, locations in rural and urban areas with
low industrial activity and moderate traffic. In winter, heating in concentrated urban
areas can cause increased contamination. Salt mist can be present in sheltered
locations of coastal areas and in offshore sites.
7C8 applies to use at, and direct transfer between, locations with normal level of
contaminants in urban areas with industrial activity spread over the whole area, or with
heavy traffic.
7C9 applies to use at, and direct transfer between, locations in the immediate
neighbourhood of industrial sources with chemical emissions.
7C10 applies to use at, and direct transfer between, locations within industrial plants where
emissions of chemical pollutants in high concentration can occur.
The values given have been taken from surveys over several years. Maximum values are given,
because direct influence of higher concentrations over a short period of time normally causes
more damage to material which cannot regenerate. Mean values are given additionally, because
their influence can be important for the long-term effect on internal parts of the products. In
practice, not all contaminants (parameters) classified in this document are present
simultaneously. Furthermore, the probability is low that the concentrations of those
contaminants actually present increase simultaneously and homogeneously. Depending on the
local situation, there are often higher values of one contaminant only.
Table 4 – Classification of chemically active substances
Class
7C5 7C6 7C7 7C8 7C9 7C10
Environmental
a
Unit
parameter
Mean Maximum Mean Mean
Maximum Maximum Maximum Maximum Maximum
b b
value value
value value
b b b b b
value value value value value
b b
Salt mist due
d d d
None Negligible Negligible Negligible Yes Yes Yes
to sea salts
Salt mist due
d d d
None Negligible Negligible Negligible Yes Yes Yes
to road salts
Saltwater None No No No No No No
Sulphur 0,01 0,1 0,1 0,3 1,0 5,0 10 13 40
mg/m
dioxide
3 3 0,003 7 0,037 0,037 0,11 0,37 1,85 3,7 4,8 14,8
cm /m
Hydrogen 0,001 5 0,01 0,01 0,1 0,5 3,0 10 14 70
mg/m
sulphide
3 3
0,001 0,007 1 0,007 1 0,007 1 0,36 2,1 7,1 9,9 49,7
cm /m
Chlorine 0,001 0,01 0,1 0,1 0,3 0,3 1,0 0,6 3,0
mg/m
3 3
0,000 34 0,003 4 0,034 0,034 0,1 0,1 0,34 0,2 1,0
/m
cm
Hydrogen 0,001 0,01 0,1 0,1 0,5 1,0 5,0 1,0 5,0
mg/m
chloride
3 3 0,000 66 0,006 6 0,066 0,066 0,33 0,66 3,3 0,66 3,3
cm /m
Hydrogen 0,001 0,003 0,003 0,01 0,03 0,1 2,0 0,1 2,0
mg/m
fluoride
3 3
0,001 2 0,003 6 0,003 6 0,012 0,036 0,12 2,4 0,12 2,4
cm /m
Ammonia 0,03 0,3 0,3 1,0 3,0 10 35 35 175
mg/m
3 3
0,042 0,42 0,42 1,4 4,2 14 49 49 247
cm /m
Ozone 0,004 0,01 0,01 0,05 0,1 0,1 0,3 0,2 2,0
mg/m
3 3
0,002 0,005 0,005 0,025 0,05 0,05 0,15 0,1 1,0
cm /m
Nitrogen 0,01 0,1 0,1 0,5 1,0 3,0 9,0 10 20
mg/m
c
oxides
3 3
0,005 0,052 0,052 0,26 0,52 1,56 4,68 5,2 10,4
cm /m
a 3 3 3
The values given in cm /m have been calculated from the values given in mg/m referenced to a temperature
of 20 °C and a pressure of 101,3 kPa. The table uses rounded values.
b
Mean values are expected long-term values. Maximum values are limit or peak values occurring over a period
of time that is typically not more than 30 min per day.
c
Expressed in equivalent values of nitrogen dioxide.
d
Additional details regarding the categorization of these conditions can be found in ISO 9223.

5.6 Mechanically active substances (S)
NOTE The classes defined in IEC 60721-3-7:1987 and IEC 60721-3-7:1995 have been replaced with new classes
as a result of recent efforts at collecting information regarding mechanically active substances.
Dust and sand are classified together, as the effects caused by these environmental conditions
are similar. These conditions are specified in Table 5.
7S1 applies to use at, and direct transfer between, locations without special precautions to
protected from dust and sand.
7S2 applies to use at, and direct transfer between, locations which are in close proximity
to dust and sand sources.
7S3 applies to use at, and direct transfer between, locations with processes producing dust
and sand or in geographical areas with a high proportion of wind-driven sand or dust
in the air.
Table 5 – Classification of mechanically active substances
Class
Environmental parameter Unit
7S1 7S2 7S3
Sand in air 30 300 10 000
mg/m
Dust in air 0,2 5,0 20
mg/m
Dust (sedimentation rate) 1,5 20 80
mg/(m ⋅h)
5.7 Mechanical conditions (M)
NOTE The classes defined in IEC 60721-3-7:1987 and IEC 60721-3-7:1995 have been replaced with new classes
as a result of recent efforts at collecting information regarding mechanical conditions. Those results are contained
in Technical Reports referenced in this document.
Mechanical conditions described in this document encompass those conditions that can exist
during use at or transfer between locations and are described in Table 6. The conditions do not
represent test severities. The vibration environments, both sinusoidal and random, as well as
the mechanical shock environments are depicted in Figure 1, Figure 2 and Figure 3
respectively.
7M4 applies to use at, and direct transfer between, locations with only low levels of vibration
or with medium level shocks. Handling and transfer of products is undertaken with
care.
7M5 applies to use at, and direct transfer between, locations with moderate vibration levels
or with high shock levels. Handling and transfer of products is undertaken with less
care.
7M6 applies to use at, and direct transfer between, locations with significant vibration levels
or with high shock levels. Handling and transfer of products is undertaken with no
control.
Table 6 – Classification of mechanical conditions
Class
Environmental
Unit
parameter
7M4 7M5 7M6
Stationary vibration, sinusoidal:
Displacement amplitude mm 3,5 - - 3,5 - - 7,5 - -
Acceleration amplitude - 10 15 - 10 15 - 20 40
m/s
9 to 200 to 9 to 200 to 200 to
Frequency range Hz 2 to 9 2 to 9 2 to 8 9 to 200
200 500 200 500 500
Stationary vibration, random:
2 2
Acceleration power
(m/s ) /
1,0 0,3 3,0 1 10 5
spectral density
Hz
200 to 200 to
a
Hz 10 to 200 10 to 200 10 to 200 200 to 2 000
Frequency range
2 000 2 000
c
Non-stationary vibration including shock:
Class
Environmental
Unit
parameter
7M4 7M5 7M6
b c
Figure 3, curve 1 Figure 3, curve 1 Figure 3, curve 3
Shock 1
(equivalent to a half (equivalent to a half (equivalent to a half sine
2 2 2
sine pulse of 100 m/s sine pulse of 100 m/s pulse of 300 m/s and
and 11 ms duration) and 11 ms duration) 11 ms duration)
b c
None Figure 3, curve 2 Figure 3, curve 4
Shock 2
(equivalent to a half (equivalent to a half sine
2 2
sine pulse of 300 m/s pulse of 1 000 m/s and
and 6 ms duration) 6 ms duration)
Free fall:
Mass less than 1 kg m 0,025 0,25 1,0
Mass 1 to 10 kg m 0,025 0,1 0,5
Mass 10 kg to 50 kg m 0,025 0,05 0,25
d
m 0,025 0,025 0,1
Mass more than 50 kg
a
When transfer only occurs by rail, river, sea and road, the upper frequency considered can be reduced to 500 Hz
for products that are not sensitive to vibration excitations above 500 Hz.
b
For land vehicle transfer, these shocks can occur simultaneously with the stationary vibration random
conditions.
c
Both shocks would normally be used to encompass different aspects of the shock environment.
d
Values are for guidance and actual severities can be based upon consideration of product life cycle.

Figure 1 – Stationary vibration, sinusoidal
Figure 2 – Stationary vibration, random

Figure 3 – Non-stationary shock conditions

Bibliography
IEC 60721-2-1, Classification of environmental conditions - Part 2-1: Environmental conditions
appearing in nature - Temperature and humidity.
IEC 60721-2-2, Classification of environmental conditions - Part 2-2: Environmental conditions
appearing in nature - Precipitation and wind.
IEC 60721-2-3, Classification of environmental conditions - Part 2-3: Environmental conditions
appearing in nature - Air pressure.
IEC 60721-2-4, Classification of environmental conditions - Part 2-4: Environmental conditions
appearing in nature - Solar radiation and temperature.
IEC 60721-2-5, Classification of environmental conditions - Part 2-5: Environmental conditions
appearing in nature - Dust, sand, salt mist
IEC 60721-3 (all parts), Classification of environmental conditions - Part 3: Classification of
groups of environmental parameters and their severities.
IEC 60721-3-0, Classification of environmental conditions - Part 3-0: Classification of groups of
environmental parameters and their severities - Introduction.
IEC 60721-3-7:1987, Classification of environmental conditions - Part 3-7: Classification of
groups of environmental parameters and their severities - Portable and non-stationary use
IEC 6721-3-7:1995, Classification of environmental conditions - Part 3: Classification of groups
of environmental parameters and their severities - Section 7: Portable and non-stationary use
IEC TR 62130, Climatic field data including validation
IEC TR 62131-3, Environmental conditions - Vibration and shock of electrotechnical
equipment - Part 3: Equipment transported in rail vehicles
IEC TR 62131-4, Environmental conditions - Vibration and shock of electrotechnical
equipment - Part 4: Equipment transported in road vehicles
IEC TR 62131-5, Environmental conditions - Vibration and shock of electrotechnical
equipment - Part 5: Equipment during storage and handling
IEC TR 62131-8, Environmental conditions - Vibration and shock of electrotechnical
equipment - Part 8: Transported by ship
ISO 9223, Corrosion of metals and alloys

___________
_________
This publication has been withdrawn.
SOMMAIRE
AVANT-PROPOS . 2
1 Domaine d'application . 4
2 Références normatives . 4
3 Termes et définitions. 4
4 Généralités . 5
5 Classification des groupements des agents d'environnement et de leurs sévérités . 6
5.1 Généralités . 6
5.2 Conditions climatiques (K) . 6
5.3 Conditions climatiques spéciales (Z) . 10
5.4 Conditions biologiques (B) . 10
5.5 Substances chimiquement actives (C). 11
5.6 Substances mécaniquement actives (S) . 12
5.7 Conditions mécaniques (M) . 13
Bibliographie . 16

Figure 1 – Vibrations stationnaires, sinusoïdales . 14
Figure 2 – Vibrations stationnaires, aléatoires . 15
Figure 3 – Conditions de choc non stationnaires . 15

Tableau 1 – Classification des conditions climatiques. 8
Tableau 2 – Classification des conditions climatiques spéciales . 10
Tableau 3 – Classification des conditions biologiques . 11
Tableau 4 – Classification des substances chimiquement actives . 12
Tableau 5 – Classification des substances mécaniquement actives . 13
Tableau 6 – Classification des conditions mécaniques . 13

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
Classification des conditions d'environnement -
Partie 3-7: Classification des groupements des agents d'environnement
et de leurs sévérités - Utilisation en déplacement

AVANT-PROPOS
1) La Commission Électrotechnique Internationale (IEC) est une organisation mondiale de normalisation composée
de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l'IEC). L'IEC
...

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