雷电防护

CONTENTS

	Page
SECTION 1 SCOPE AND GENERAL
1.1 SCOPE	5
1.2 APPLICATION	5
1.3 INTRODUCTION	5
1.4 REFERENCED DOCUMENTS	6
1.5 DEFINITIONS	6
SECTION 2 ASSESSMENT AND MANAGEMENT OF RISK DUE TO LIGHTNING — ANALYSIS OF NEED FOR PROTECTION
2.1 INTRODUCTION	11
2.2 SCOPE OF SECTION	11
2.3 CONCEPT OF RISK	12
2.4 DAMAGE DUE TO LIGHTNING	13
2.5 RISKS DUE TO LIGHTNING	17
2.6 PROCEDURE FOR RISK ASSESSMENT AND MANAGEMENT	21
2.7 RISK MANAGEMENT CALCULATION TOOL	23
SECTION 3 PRECAUTIONS FOR PERSONAL SAFETY
3.1 SCOPE OF SECTION	28
3.2 NEED FOR PERSONAL PROTECTION	28
3.3 PERSONAL CONDUCT	29
3.4 EFFECT ON PERSONS AND TREATMENT FOR INJURY BY LIGHTNING	31
SECTION 4 PROTECTION OF STRUCTURES
4.1 SCOPE OF SECTION	32
4.2 PROTECTION LEVEL	32
4.3 LPS DESIGN RULES	32
4.4 ZONES OF PROTECTION FOR LIGHTING INTERCEPTION	34
4.5 METHODS OF PROTECTION	42
4.6 MATTERS TO BE CONSIDERED WHEN PLANNING PROTECTION	44
4.7 MATERIALS	47
4.8 FORM AND SIZE OF CONDUCTORS	51
4.9 JOINTS	52
4.10 FASTENERS	52
4.11 AIR TERMINALS	53
4.12 DOWNCONDUCTORS	55
4.13 TEST LINKS	58
4.14 EARTH TERMINATIONS	58
4.15 EARTHING ELECTRODES	59
4.16 METAL IN AND ON A STRUCTURE	61
SECTION 5 PROTECTION OF PERSONS AND EQUIPMENT WITHIN BUILDINGS
5.1 SCOPE OF SECTION	66
5.2 NEED FOR PROTECTION	66
5.3 MODES OF ENTRY OF LIGHTNING IMPULSES	66
5.4 GENERAL CONSIDERATIONS FOR PROTECTION	69
5.5 PROTECTION OF PERSONS WITHIN BUILDINGS	70
5.6 PROTECTION OF EQUIPMENT	73

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Australian/New Zealand Standard™

Lightning protection

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AS/NZS 1768:2007

This Joint Australian/New Zealand Standard was prepared by Joint Technical Committee EL-024, Protection Against Lightning. It was approved on behalf of the Council of Standards Australia on 13 September 2006 and on behalf of the Council of Standards New Zealand on 6 October 2006. This Standard was published on 10 January 2007.

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The following are represented on Committee EL-024:

Association of Consulting Engineers Australia

Australasian Corrosion Association

Australasian Railway Association

Australian Chamber of Commerce and Industry

Australian Electrical and Electronic Manufacturers Association

Australian Institute of Petroleum Ltd

Bureau of Meteorology

CSIRO Industrial Physics

Department of Defence (Australia)

Department of Natural Resources and Mines (QLD)

Department of Primary Industries, Mine Safety (NSW)

Energy Networks Association

Engineers Australia

ITU NSG5

Master Builders Australia

Ministry of Economic Development (New Zealand)

National Electrical and Communications Association

Telstra Corporation Limited

The University of Queensland

Transpower New Zealand

UniQuest

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Detailed information about joint Australian/New Zealand Standards can be found by visiting the Standards Web Shop at www.standards.com.au or Standards New Zealand web site at www.standards.co.nz and looking up the relevant Standard in the on-line catalogue.

Alternatively, both organizations publish an annual printed Catalogue with full details of all current Standards. For more frequent listings or notification of revisions, amendments and withdrawals, Standards Australia and Standards New Zealand offer a number of update options. For information about these services, users should contact their respective national Standards organization.

We also welcome suggestions for improvement in our Standards, and especially encourage readers to notify us immediately of any apparent inaccuracies or ambiguities. Please address your comments to the Chief Executive of either Standards Australia or Standards New Zealand at the address shown on the back cover.

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This Standard was issued in draft form for comment as DR 06132.

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Australian/New Zealand Standard™

AS/NZS 1768:2007

Lightning protection

Originated in Australia as MC1—1969.

Originated in New Zealand as NZS/AS 1768:1991.

Previous edition AS/NZS 1768(Int):2003.

This edition AS/NZS 1768:2007.

COPYRIGHT

© Standards Australia/Standards New Zealand

All rights are reserved. No part of this work may be reproduced or copied in any form or by any means, electronic or mechanical, including photocopying, without the written permission of the publisher.

Jointly published by Standards Australia, GPO Box 476, Sydney, NSW 2001 and Standards New Zealand, Private Bag 2439, Wellington 6020

ISBN 0 7337 7967 0

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PREFACE

This Standard was prepared by the Joint Standards Australia/Standards New Zealand Committee EL-024, Protection against Lightning, to supersede AS/NZS 1768(Int):2003, Lightning protection.

This Standard is intended to provide authoritative guidance on the principles and practices of lightning protection for a wide range of structures and systems. It is not intended for mandatory application but, if called up in a contractual situation, compliance with this Standard requires compliance with all relevant clauses of the Standard such that the level of protection will be sufficient to achieve a tolerable level of risk as determined by the risk calculation.

In general, it is not economically possible to provide total protection against all the possible damaging effects of lightning, but the recommendations in this Standard will reduce the probability of damage to a calculated acceptable level, and will minimize any lightning damage that does occur. Guidance is given on methods of enhancing the level of protection against lightning damage, if this is required in a particular situation.

Where a new structure is to be erected, the matter of lightning protection should be considered in the planning stage, as the necessary measures can often be affected in the architectural features without detracting from the appearance of the building. In addition to the aesthetic considerations, it is usually less expensive to install a lightning protection system during construction than afterwards.

The decision to provide lightning protection may be taken without carrying out a risk assessment or regardless of the outcome of any risk assessment, for example, where there is a desire that there be no avoidable risk. Any decision not to provide lightning protection should only be made after considering the advice provided in this Standard. Where doubt exists as to the need for lightning protection, further advice should be sought from a lightning protection designer or installer.

Unless it has been specified that lightning protection must be provided, the first decision to make is whether the lightning protection is needed. Section 2 provides guidance to assist in this decision. Section 3 provides advice on the protection of persons from lightning, mainly relating to the behaviour of persons when not inside substantial buildings. Once a decision is made that lightning protection is necessary, Section 4 provides details on interception lightning protection for the building or structure. This includes information on the size, material, and form of conductors, the positioning of air terminals and downconductors, and the requirements for earth terminations. Persons and equipment within buildings can be at risk from the indirect effects of lightning and Section 5 gives recommendations for the protection of persons and equipment within buildings from the effects of lightning.

Section 6 describes methods of lightning protection of various items not covered in earlier sections, such as communications antennas, chimneys, boats, fences, and trees. A clause is included on methods for protecting domestic dwellings and assorted structures in public places, where a complete protection system may not be justified, but some protection is considered desirable.

Section 7 sets out recommendations for the protection of structures with explosive or highly-flammable contents. Section 8 gives advice on precautions to be taken during installation, inspecting, testing, and maintaining lightning protection systems.

A number of appendices are included that provide additional information and advice. The appendices form an integral part of this Standard unless specifically stated otherwise. i.e. appendices identified as 'informative' only provide supportive or background information and are therefore not an integral part of this Standard.

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CONTENTS

	Page
SECTION 1 SCOPE AND GENERAL
1.1 SCOPE	5
1.2 APPLICATION	5
1.3 INTRODUCTION	5
1.4 REFERENCED DOCUMENTS	6
1.5 DEFINITIONS	6
SECTION 2 ASSESSMENT AND MANAGEMENT OF RISK DUE TO LIGHTNING — ANALYSIS OF NEED FOR PROTECTION
2.1 INTRODUCTION	11
2.2 SCOPE OF SECTION	11
2.3 CONCEPT OF RISK	12
2.4 DAMAGE DUE TO LIGHTNING	13
2.5 RISKS DUE TO LIGHTNING	17
2.6 PROCEDURE FOR RISK ASSESSMENT AND MANAGEMENT	21
2.7 RISK MANAGEMENT CALCULATION TOOL	23
SECTION 3 PRECAUTIONS FOR PERSONAL SAFETY
3.1 SCOPE OF SECTION	28
3.2 NEED FOR PERSONAL PROTECTION	28
3.3 PERSONAL CONDUCT	29
3.4 EFFECT ON PERSONS AND TREATMENT FOR INJURY BY LIGHTNING	31
SECTION 4 PROTECTION OF STRUCTURES
4.1 SCOPE OF SECTION	32
4.2 PROTECTION LEVEL	32
4.3 LPS DESIGN RULES	32
4.4 ZONES OF PROTECTION FOR LIGHTING INTERCEPTION	34
4.5 METHODS OF PROTECTION	42
4.6 MATTERS TO BE CONSIDERED WHEN PLANNING PROTECTION	44
4.7 MATERIALS	47
4.8 FORM AND SIZE OF CONDUCTORS	51
4.9 JOINTS	52
4.10 FASTENERS	52
4.11 AIR TERMINALS	53
4.12 DOWNCONDUCTORS	55
4.13 TEST LINKS	58
4.14 EARTH TERMINATIONS	58
4.15 EARTHING ELECTRODES	59
4.16 METAL IN AND ON A STRUCTURE	61
SECTION 5 PROTECTION OF PERSONS AND EQUIPMENT WITHIN BUILDINGS
5.1 SCOPE OF SECTION	66
5.2 NEED FOR PROTECTION	66
5.3 MODES OF ENTRY OF LIGHTNING IMPULSES	66
5.4 GENERAL CONSIDERATIONS FOR PROTECTION	69
5.5 PROTECTION OF PERSONS WITHIN BUILDINGS	70
5.6 PROTECTION OF EQUIPMENT	73

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