IEC 60721-2-6:2022

Classification of environmental conditions - Part 2-6: Environmental conditions appearing in nature - Earthquake vibration and shock

IEC 60721-2-6:2022 deals with environmental conditions appearing in nature related to earthquake vibrations and shocks.
Its object is to define some fundamental properties and quantities for characterization of earthquakes as background material for the severities to which products are liable to be exposed during storage and use. The accelerations given are for ground surface conditions only. Conditions related to structures are referred to but restricted to general case descriptions.
This second edition cancels and replaces the first edition published in 1990. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
the main aim of this revision is to classify in a limited number of classes the seismic activity level of the zone where the equipment could be installed;
the correlation between intensity scales, magnitude scales and peak ground acceleration is deleted due to the scientific uncertainty to define such a correlation in a rigorous way;
updated scales are given both for intensity and for magnitude;
the earthquake zone map, which was not usable in practice, is replaced by an annex giving information about how to retrieve consistent peak ground acceleration distribution all over the world;
with regard to identification of the peak ground seismic acceleration of the zone, where the equipment could be installed, the user is made aware that national standards and laws can apply.
The contents of the corrigendum of October 2023 have been included in this copy.

Classification des conditions d'environnement. Partie 2-6: Conditions d'environnement présentes dans la nature. Vibrations et chocs sismiques

L'IEC 60721-2-6:2022 traite des conditions d'environnement présentes dans la nature et qui sont liées à des vibrations et des chocs sismiques.
Elle a pour objet de définir des propriétés fondamentales et des grandeurs pour la caractérisation des séismes comme base pour les sévérités auxquelles les matériels sont susceptibles d'être exposés durant leur stockage et leur utilisation. Les accélérations données concernent uniquement les conditions à la surface du sol. Les conditions relatives aux structures sont mentionnées, mais leurs descriptions sont limitées aux cas généraux.
Cette deuxième édition annule et remplace la première édition parue en 1990. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
le principal objectif de la présente révision est de classer dans un nombre limité de classes le niveau d'activité sismique de la zone où le matériel est susceptible d'être installé;
la corrélation entre les échelles d'intensité, les échelles de magnitude et l'accélération crête du sol a été supprimée en raison de l'incertitude scientifique qui existe pour la définir de manière rigoureuse;
des échelles mises à jour sont données pour l'intensité et pour la magnitude;
la carte des zones de séismes, qui n'était pas utilisable en pratique, a été remplacée par une annexe qui fournit des informations qui permettent d'obtenir une répartition cohérente de l'accélération crête du sol dans le monde entier;
en ce qui concerne l’identification de l'accélération sismique crête du sol de la zone où le matériel est susceptible d'être installé, l’utilisateur est informé que des normes et des lois nationales peuvent s’appliquer.
Le contenu du corrigendum d'octobre 2023 a été pris en considération dans cet exemplaire.

General Information

• Status: Published
• Publication Date: 14-Dec-2022
• ICS: 19.040 - Environmental testing
• Technical Committee: TC 104 - Environmental conditions, classification and methods of test
• Drafting Committee: MT 17 - TC 104/MT 17
• Current Stage: PPUB - Publication issued
• Start Date: 13-Jan-2023
• Completion Date: 15-Dec-2022

Relations

• Corrected By: IEC 60721-2-6:2022/COR1:2023 - Corrigendum 1 - Classification of environmental conditions - Part 2-6: Environmental conditions appearing in nature - Earthquake vibration and shock
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60721-2-6 ®
Edition 2.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –
Part 2-6: Environmental conditions appearing in nature – Earthquake vibration
and shock
Classification des conditions d'environnement –
Partie 2-6: Conditions d'environnement présentes dans la nature – Vibrations et
chocs sismiques
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IEC 60721-2-6 ®
Edition 2.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Classification of environmental conditions –

Part 2-6: Environmental conditions appearing in nature – Earthquake vibration

and shock
Classification des conditions d'environnement –

Partie 2-6: Conditions d'environnement présentes dans la nature – Vibrations et

chocs sismiques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 19.040 ISBN 978-2-8322-6272-6

– 2 – IEC 60721-2-6:2022 © IEC 2022
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 General description of earthquake . 6
4.1 General . 6
4.2 Earthquake origin and propagation . 7
4.3 Earthquake behaviour . 7
4.4 Products on foundations . 7
4.5 Products in buildings and structures . 7
5 Seismic scales . 7
5.1 Definition of intensity and magnitude . 7
5.2 Examples of intensity scales . 8
5.3 Example of magnitude scale . 9
6 Description of the seismic environment by response spectra . 10
6.1 Response spectrum . 10
6.2 Ground response spectrum . 10
6.3 Required response spectrum . 11
7 Seismic activity zone classification . 11
Annex A (informative) Example of seismic activity zones . 16
A.1 Classification criteria of US Uniform Building Code . 16
A.2 World seismic activity zones classification according to UBC . 16
Bibliography . 25

Figure 1 – Acceleration record of the Irpinia-Basilicata-Italy earthquake (1980) . 12
Figure 2 – Model for composing a response spectrum . 13
Figure 3 – Response spectrum of the Calitri record of Irpinia earthquake (1980)
(Figure 1) for 2 % damping ratio value . 14
Figure 4 – Example of required response spectrum for ground motion . 15

Table 1 – Earthquake intensity scales for some countries/regions . 8
Table 2 – European Macroseismic Scale (EMS-98) . 9
Table 3 – Moment Magnitude Scale . 10
Table 4 – Seismic activity zones . 11
Table A.1 – Seismic activity zones definition according to UBC. 16
Table A.2 – Seismic activity zones classification according to UBC . 16

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CLASSIFICATION OF ENVIRONMENTAL CONDITIONS –

Part 2-6: Environmental conditions appearing in nature –
Earthquake vibration and shock

FOREWORD
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IEC 60721-2-6 has been prepared by IEC technical committee 104: Environmental conditions,
classification and methods of test. It is an International Standard.
This second edition cancels and replaces the first edition published in 1990. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the main aim of this revision is to classify in a limited number of classes the seismic activity
level of the zone where the equipment could be installed;
b) the correlation between intensity scales, magnitude scales and peak ground acceleration is
deleted due to the scientific uncertainty to define such a correlation in a rigorous way;
c) updated scales are given both for intensity and for magnitude;

– 4 – IEC 60721-2-6:2022 © IEC 2022
d) the earthquake zone map, which was not usable in practice, is replaced by an annex giving
information about how to retrieve con
...