TC 81 - Lightning protection

IEC 62561-5:2023 is available as IEC 62561-5:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62561-5:2023 specifies the requirements and tests for earth electrode inspection housings (earth housings) installed in the earth and for earth electrode seals. Lightning protection system components (LPSC) can also be suitable for use in hazardous atmospheres. For this reason, there are additional requirements when installing the components under such conditions. This third edition cancels and replaces the second edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) A classification of earth electrode seals has been added.

IEC 62561-3:2023 is available as IEC 62561-3:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 62561-3:2023 specifies the requirements and tests for isolating spark gaps (ISGs) for lightning protection systems. ISGs can be used to indirectly bond a lightning protection system to other nearby metalwork where a direct bond is not permissible for functional reasons. This third edition cancels and replaces the second edition, published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition.
a) alignment with the latest edition of ISO 22479 relating to humid sulphurous atmosphere treatment;
b) addition of a new normative Annex D for the applicability of previous tests.

IEC 62561-6:2023 is available as IEC 62561-6:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 62561-6:2023 specifies the requirements and tests for devices intended to count the number of lightning strikes based on the current flowing in a conductor. This conductor can be part of a lightning protection system (LPS) or connected to an SPD installation or other conductors, which are not intended to conduct a significant portion of lightning currents. This third edition cancels and replaces the second edition published in 2018. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) a new classification according to the internal circuit of LSCs has been added;
b) the tests flowchart in Annex C has been updated to reflect this new classification;
c) the applicability of previous tests has been added (Annex D).

IEC 62561-1:2023 is available as IEC 62561-1:2023 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 62561-1:2023 specifies the requirements and tests for metallic connection components that form part of a lightning protection system (LPS). Typically, these can be connectors, clamps, bonding and bridging components, expansion pieces and test joints. This third edition cancels and replaces the second edition published in 2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
a) definitions of connection types mentioned in the scope have been added;
b) location classification has been expanded in detail;
c) the document has been updated in line with the new edition of ISO 22479:2019 on humid sulphurous atmosphere treatment;
d) a new normative Annex E for reduced test procedures has been introduced.

IEC 62305-3:2024 provides the requirements for protection of a structure against physical damage by means of a lightning protection system (LPS), and for protection against injury to human beings due to touch and step voltages in the vicinity of an LPS (see IEC 62305-1).
This document is applicable to the:
a) design, installation, inspection and maintenance of an LPS for structures without limitation of their height,
b) establishment of measures for protection against injury to human beings primarily due to touch and step voltages.
This third edition cancels and replaces the second edition published in 2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Minimum thicknesses of metal sheets or metal pipes are given in Table 4 for air-termination systems where it is necessary to prevent hot-spot problems. Maximum temperature rises ΔT (K) and time duration t50 (s) for different thicknesses and long strokes are also given.
b) Cross-reference to the IEC 62561 series is made for the use of reliable, stable, safe and appropriate LPS components.
c) The application of two methods – general and simplified – for separation distance calculation is clarified.
d) Some changes to the requirements for continuity of steel reinforcement are made.
e) Annex C is revised to address comments from IEC subcommittee 31J.
f) Revision of positioning of air-termination conductors are modified according to the three accepted methods. A more precise description of the methods for positioning of the air-termination systems are made according to the complexity of structures to be protected. The main text has been simplified, Annex A has been deleted and all detailed information has been moved to Annex D.
g) Information on the protection of green roofs is introduced in Annex D.
h) Information on the protection of protruding parts on facades of tall buildings is introduced in Annex D.

IEC 62793:2020 describes the characteristics of thunderstorm warning systems (TWSs) in order to implement lightning hazard preventive measures.
Single sensors and/or a network of sensors (e.g. lightning location system) can be used as a TWS.
This second edition cancels and replaces the first edition, published in 2016. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
- portable devices are no longer covered by this standard;
- in Clause 5, classes of TWS have been deleted;
- in Clause 6, updated figures and more detailed text are provided to better illustrate the alarm timeline;
- in Clause 9, the text has been summarized and refers now to the application guide given in Annex F;
- annexes have been reorganized;
- Annex E is normative.

IEC 62858:2019 is available as IEC 62858:2019 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 62858:2019 introduces and discusses all necessary measures to make reliable and homogeneous the values of ground flash density, NG and ground strike point density, NSG, obtained from lightning location systems (LLSs) in various countries. Only parameters that are relevant to risk assessment are considered. This second edition cancels and replaces the first edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- Two informative annexes are introduced dealing with the determination of lightning density for risk calculation (Annex A) and ground strike point calculation methods (Annex B).

IEC 62561-7:2018 specifies the requirements and tests for earthing enhancing compounds producing low resistance of an earth termination system.
This second edition cancels and replaces the first edition, published in 2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) information concerning the execution of the test for the determination of the resistivity in 5.4.3;
b) addition of Annex A for the assessment of the corrosion load.

IEC 62561-6:2018 specifies the requirements and tests for devices intended to count the number of lightning strikes based on the current flowing in a conductor. This conductor may be part of a lightning protection system (LPS) or connected to an SPD installation or other conductors, which are not intended to conduct a significant portion of lightning currents.
LSCs may also be suitable for use in hazardous atmospheres and there are therefore extra requirements necessary for the components to be installed in such conditions.
This second edition cancels and replaces the first edition published in 2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) removal of previous classification and introduction of a simple division into Type I for impulses (direct lightning current detection) and Type II for lightning surge current detection, with appropriate testing for each type;
b) modification and addition of terms and definitions;
c) addition of a new Annex C (tests flow chart).

IEC 62561-2:2018 specifies the requirements and tests for:
- metallic conductors (other than "natural" conductors) that form part of the air-termination and down-conductor systems,
- metallic earth electrodes that form part of the earth-termination system.
This second edition cancels and replaces the first edition published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical change with respect to the previous edition:
a) Tables 2 and 4 have been merged into one Table (Table 2).
b) Figure 2 showing the coating measurement of a plate conductor has been added
The contents of the corrigendum of August 2019 have been included in this copy.

IEC/TS 62561-8:2018 specifies the requirements and tests for insulating stand-offs, used in conjunction with an air-termination system and down-conductors with the aim of maintaining the proper separation distance, and the requirements and tests for insulating down‑conductors, including their specific fasteners, able to reduce the separation distance.

IEC 62561-5:2017 specifies the requirements and tests for earth electrode inspection housings (earth housing) installed in the earth and for earth electrode seals.
Lightning protection system components (LPSC) can also be suitable for use in hazardous atmospheres. There are therefore additional requirements when installing the components under such conditions.
This second edition cancels and replaces the first edition, published in 2011. This edition constitutes a technical revision.
This edition includes the following major technical changes with respect to the previous edition.
- Testing requirements have been added for the sealing of earth electrode installed in or through watertight concrete.

IEC 62561-4:2017 deals with the requirements and tests for metallic and non-metallic conductor fasteners that are used to retain and support the air-termination, down-conductor and earth-termination systems.
This document does not cover the fixing of conductor fasteners to the fabric of structures due to the vast number and types used in modern day construction.
LPSC can also be suitable for use in hazardous atmospheres. There are therefore additional requirements when installing the components in such conditions.
This second edition cancels and replaces the first edition, published in 2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
- new detailed flow chart of the tests;
- in Annexes A and B, composite fasteners have been added.

IEC 62561-3:2017 specifies the requirements and tests for isolating spark gaps (ISG) for lightning protection systems.
ISGs can be used to indirectly bond a lightning protection system to other nearby metalwork where a direct bond is not permissible for functional reasons.
This bilingual version (2018-11) corresponds to the monolingual English version, published in 2017-06.
This second edition cancels and replaces the first edition, published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition.
- a new classification has been added related to ISGs location installation;
- an updated flow chart of tests has been developed.
The French version of this document has not been voted upon.

IEC 62561-1:2017 is also available as IEC 62561-1:2017 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.
IEC 62561-1:2017 specifies the requirements and tests for metallic connection components that form part of a lightning protection system (LPS). Typically, these can be connectors, clamps, bonding and bridging components, expansion pieces and test joints.
For the purposes of this document the following connection types are considered as connection components: exothermic, brazing, welding, clamping, crimping, seaming, screwing or bolting. Testing of components for an explosive atmosphere is not covered by this document.
This second edition cancels and replaces the first edition, published in 2012. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a. classification of connection components in permanent and non-permanent connection;
b. requirements and corresponding tests for permanent connection components such as exothermic, brazing, welding, crimping, seaming;
c. flow chart of tests for connection components.

IEC 62793:2016 describes the characteristics of thunderstorm warning systems and evaluation of the usefulness of lightning real time data and/or storm electrification data in order to implement lightning hazard preventive measures. This standard provides the basic requirements for sensors and networks collecting accurate data of the relevant parameters, giving real-time information of lightning tracks and range. It describes the application of the data collected by these sensors and networks in the form of warnings and historical data. This standard applies to the use of information from thunderstorm warning systems (systems or equipment providing real-time information) on atmospheric electric activity in order to monitor preventive measures.
This bilingual version (2018-11) corresponds to the monolingual English version, published in 2016-05.
The French version of this standard has not been voted upon.

IEC/TR 62713:2013 introduces lightning to the layman, noting the right action in the presence of thunderstorms, as well as protective measures against lightning. It also contributes to the prevention of lightning injuries and damages. It should be noted that so far there are no means to avoid lightning. However, by following some elementary rules, people can be protected against its deleterious effects.

IEC 62561-3:2012 specifies the requirements and tests for isolating spark gaps (ISG) for lightning protection systems. ISGs can be used to indirectly bond a lightning protection system to other nearby metalwork where a direct bond is not permissible for functional reasons.

IEC 62561-1:2012 specifies the requirements and tests for metallic connection components that form part of a lightning protection system (LPS). Typically, these can be connectors, bonding and bridging components, expansion pieces and test joints. Testing of components for an explosive atmosphere is not covered by this standard.

IEC 62561-2:2012 specifies the requirements and tests for:
- metallic conductors (other than "natural" conductors) that form part of the air termination system and down conductors;
- metallic earth electrodes that form part of the earth termination system.

IEC 62561-7:2011 specifies the requirements and tests for earthing enhancing compounds producing low resistance of an earth termination system.

IEC 62561-5:2011 specifies the requirements and tests for
- earth electrode inspection housings (earth pit),
- earth electrode seals.
Lightning protection system components (LPSC) may also be suitable for use in hazardous atmospheres. Regard should then be taken of the extra requirements necessary for the components to be installed in such conditions.

IEC 62561-6:2011 specifies the requirements and tests for devices intended to count the number of lightning strike pulses flowing in a conductor. This conductor may be part of a lightning protection system (LPS) or connected to an SPD installation (or other conductors which are not intended to conduct a significant portion of lightning currents).

IEC 62305-2:2010 is applicable to risk assessment for a structure due to lightning flashes to earth. Its purpose is to provide a procedure for the evaluation of such a risk. Once an upper tolerable limit for the risk has been selected, this procedure allows the selection of appropriate protection measures to be adopted to reduce the risk to or below the tolerable limit. This second edition cancels and replaces the first edition, published in 2006, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
1) Risk assessment for services connected to structures is excluded from the scope.
2) Injuries of living beings caused by electric shock inside the structure are considered.
3) Tolerable risk of loss of cultural heritage is lowered from 10-3 to 10-4. The value of tolerable risk of loss of economic value (RT = 10-3) is introduced, to be used when data for cost/benefit analysis are not available.
4) Extended damage to surroundings structures or to the environment is considered.
5) Improved equations are provided for evaluation of
- collection areas relevant to flashes nearby a structure,
- collection areas relevant to flashes to and nearby a line,
- probabilities that a flash can cause damage,
- loss factors even in structures with risk of explosion,
- risk relevant to a zone of a structure,
- cost of loss.
6) Tables are provided to select the relative amount of loss in all cases.
7) Impulse withstand voltage level of equipments was extended down to 1 kV.
This bilingual version corresponds to the monolingual English version, published in 2010-12.

IEC 62305-1:2010 provides general principles to be followed for protection of structures against lightning, including their installations and contents, as well as persons. This second edition cancels and replaces the first edition, published in 2006, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
1) It no longer covers protection of services connected to structures.
2) Isolated interfaces are introduced as protection measures to reduce failure of electric and electronic systems.
3) First negative impulse current is introduced as a new lightning parameter for calculation purposes.
4) Expected surge overcurrents due to lightning flashes have been more accurately specified for low voltage power systems and for telecommunication systems.
This bilingual version (2013-01) corresponds to the monolingual English version, published in 2010-12.

IEC 62305-3:2010 provides the requirements for protection of a structure against physical damage by means of a lightning protection system (LPS), and for protection against injury to living beings due to touch and step voltages in the vicinity of an LPS (see IEC 62305-1). This second edition cancels and replaces the first edition, published in 2006, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
1) Minimum thicknesses of metal sheets or metal pipes given in Table 3 for air-termination systems are assumed as not able to prevent hot-spot problems.
2) Steel with electro-deposited copper is introduced as material suitable for LPS.
3) Some cross-sectional areas of LPS conductors were slightly modified.
4) For bonding purposes, isolating spark gaps are used for metal installations and SPD for internal systems.
5) Two methods simplified and detailed are provided for evaluation of separation distance.
6) Protection measures against injuries of living beings due to electric shock are considered also inside the structure.
7) Improved information for LPS in the case of structures with a risk of explosion are given in Annex D (normative).
This bilingual version (2012-06) corresponds to the monolingual English version, published in 2010-12.

IEC 62305-4:2010 provides information for the design, installation, inspection, maintenance and testing of electrical and electronic system protection (SPM) to reduce the risk of permanent failures due to lightning electromagnetic impulse (LEMP) within a structure. This second edition cancels and replaces the first edition, published in 2006, and constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
1) Isolating interfaces capable of reducing conducted surges on lines entering the structure are introduced.
2) Minimum cross-sections for bonding components are slightly modified.
3) First negative impulse current is introduced for calculation purposes as electromagnetic source of harm to the internal systems.
4) Selection of SPD with regard to voltage protection level is improved to take into account oscillation and induction phenomena in the circuit downstream of SPD.
5) Annex C dealing with SPD coordination is withdrawn and referred back to SC 37A.
6) A new informative Annex D is introduced giving information on factors to be considered in the selection of SPDs.
This bilingual version (2012-06) corresponds to the monolingual English version, published in 2010-12.

IEC 62561-4:2010 deals with the requirements and tests for metallic and non-metallic conductor fasteners that are used in conjunction with the air termination, down conductor and earth termination system. This standard does not cover the fixing of conductor fasteners to the fabric/membrane/gravel roofing of structures due to the vast number and types used in modern day construction. LPSC may also be suitable for use in hazardous atmospheres. Regard should then be taken of the extra requirements necessary for the components to be installed in such conditions.

Objective is to limit the number of possible primary failures occurring in the optical fibre cable in a specified installation to within values which are lower than or equal to the limit value, defined as the tolerable frequency of primary failures. Gives the method for calculating the possible number of primary failures, choosing the feasible protective measures and indicating the tolerable frequency of primary failures. Secondary failures are not considered. The tests described in annex G are convenient only for the risk evaluation associated with lightning in fibre optic installations. Tests for the qualification of a cable design are outside the scope of this standard.

Deals with the requirements of Surge Protective Devices (SPDs) standardized by IEC 61643-1. These SPDs are installed according to the Lightning Protection Zones concept given by IEC 61312-1. First, starting from primary relevant threats, gives instructions for the determination of the stress for individual SPDs. For SPDs installed within a complex system, it is admissible to divide the system into simple basic arrangements, observing the rules described. When the values and directions of the partial lightining currents flowing within the system are known, the appropriate SPDs can be selected. Also deals with basic questions of the energy coordination of SPDs among each other and between SPDs and the threat at the respective place of installation are to be considered for effective coordination. The proof of the coordination of SPDs installed in a system, is described briefly.

Provides methods for the evaluation of the effectiveness of shielding measures against LEMP for structures with information equipment such as electronic systems in case of direct and nearby lightning strikes. In addition it provides rules for bonding measures inside structures and for earthing methods relating to LEMP.

Gives guidelines for protection of information technology equipment (ITE) against lightning magnetic impulse (LEMP) effects in existing structures and includes methods suitable for new structures. A checklist helps to address specific points and to select the most economical measures for the hardening of equipment against LEMP. The checklist facilitates risk analysis and selection of the most suitable counter measures.

Applicable to the design and installation of Lightning Protection Systems (SPS) for common structures up to 60 m high, in accordance with IEC 61024-1. Provides guidelines on how to use IEC 61024-1 and assists the user with the physical design and construction, maintenance and inspection of an LPS

This report gives the procedure for evaluation of the risk of damage to a structure caused by direct and indirect lightning flashes, and to permit the bodies concerned to fix an acceptable value for the frequency of damage to structures. This publication has the status of a Technical Report - type 2.

Gives information for the design, installation, inspection, maintenance and testing of an effective lighning protection system for information systems in or on a structure.

Contains information on the classification of structures according to the consequential effects of a lightning stroke. Gives procedures for the selection of a lightning protection system. Is to be used with part 1.

This standard is applicable to the design and installation of Lightning Protection Systems (LPS) for common structures up to 60 m high.