1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationProtection against lightningPart 2: Risk managementBS EN 62305-2:2012National forewordThis British Standard is the UK implementation of EN 62305-2:2012. It isidentical to IEC 623
2、05-2:2012. It supersedes BS EN 62305-2:2006 whichis withdrawn.The UK participation in its preparation was entrusted to Technical Commit-tee GEL/81, Protection against lightning.The values assigned for certain parameters used as part of the riskevaluation process in this British Standard, are values
3、proposed by IEC(specifically in Annexes B, C and the case studies in Annex E). It is recognizedby IEC that these identified values may not be appropriate for application inall the countries that utilize this standard. Different values may be assignedby each national committee based upon each country
4、s perception andimportance they attribute to the relevant risk category.The UK committee has reviewed the relevant parts of this standard and haveprovided appropriate UK interpretations which can be found in nationalannexes at the end of this standard. National Annex NF containsinterpretations relat
5、ing to Table 4 and reproduces the lightning flash densitymap for the British Isles together with the table and map showing thethunderstorm days throughout the world. Annexes B, C and E have been re-produced as National Annexes NB, NC and NE. The revised versions containappropriate UK interpretations
6、 and in Annex NE two further examples,namely a heritage building and a bank computer centre, in order to providea full representation of the four categories of risk and associated loss. TheseNational Annexes should be used wherever and whenever the BritishStandard is adopted for designing lightning
7、protection systems. Due to the specific UK values outlined above, it is important to ensurethat any software package used in conjunction with this standard isspecifically designed to use the National Annexes in this document.A list of organizations represented on this committee can be obtainedon req
8、uest to its secretary.This publication does not purport to include all the necessary provisions ofa contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited2013ISBN 978 0 580 61193 3ICS 29.020; 91.120.40Compliance with a
9、British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the Stand-ards Policy and Strategy Committee on 28 February 2013.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN 62305-2:2012National forewor
10、dThis British Standard is the UK implementation of EN 62305-2:2012. It was derived from IEC 62305-2:2010. It supersedes BS EN 62305-2:2006, which will be withdrawn on 31 January 2014.The CENELEC common modifications have been implemented at theappropriate places in the text. The start and finish of
11、each commonmodification is indicated in the text by tags .The UK participation in its preparation was entrusted to Technical Committee GEL/81, Protection against lightning.The values assigned for certain para eters used as part of the risk evaluat onprocess in this Britis S andard, are values propos
12、ed by IEC (specifically inAnnex s B, C and the case studies in Annex E). It is recognized by IEC thatthese identified values may not be appropriate for application in all thecountries that utilize this standard. Different values may be assigned by eachnational committee based upon each countrys perc
13、eption and importancethey attribute to the relevant risk category.The UK committee has reviewed the relevant parts of this standard and haveprovided appropriate UK interpretations which can be found in nationalannexes at the end of this standard. National Annex NF containsinterpretations relating to
14、 Table 4 and reproduces the lightning flash densitymap for the British Isles together with the table and map showing thethunderstorm days throughout the world. Annexes B, C and E have beenreproduced as National Annexes NB, NC and NE. The revised versions containappropriate UK interpretations and in
15、Annex NE two further examples,namely a heritage building and a bank computer centre, in order to providea full representation of the four categories of risk and associated loss. These National Annexes should be sed wherev r and whenever the British Standard is adopted for designing lightning protect
16、ion systems.Due to the specific UK values outlined above, it is important to ensure thatany software package used in conjunction with this standard is specificallydesigned to use the National Annexes in this document.A list of organizations represented on this committee can be obtained onrequest to
17、its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 61193 3ICS 29.020; 91.120.40Compliance with a Britis
18、h Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2013.Amendments/corrigenda issued since publicationDate Text affectedEUROPEAN STANDARD EN 62305-2 NORME EUROPENNE EUROPISCHE NORM
19、 May 2012 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels 2012 CENELEC - All rights of exploitation in any form and by any means res
20、erved worldwide for CENELEC members. Ref. No. EN 62305-2:2012 E ICS 29.020; 91.120.40 Supersedes EN 62305-2:2006 + corr. Nov.2006English version Protection against lightning - Part 2: Risk management (IEC 62305-2:2010, modified) Protection contre la foudre - Partie 2: Evaluation des risques (CEI 623
21、05-2:2010, modifie) Blitzschutz - Teil 2: Risiko-Management (IEC 62305-2:2010, modifiziert) This European Standard was approved by CENELEC on 2012-03-19. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the
22、 status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CENELEC member. This European Standard exists in three official versions (English, F
23、rench, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austr
24、ia, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the U
25、nited Kingdom. EN 62305-2:2012 2 Contents Foreword 6Introduction 71 Scope 82 Normative references . 83 Terms, definitions, symbols and abbreviations . 83.1 Terms and definitions 83.2 Symbols and abbreviations . 134 Explanation of terms 164.1 Damage and loss 164.2 Risk and risk components . 184.3 Com
26、position of risk components . 205 Risk management 215.1 Basic procedure 215.2 Structure to be considered for risk assessment . 225.3 Tolerable risk RT225.4 Specific procedure to evaluate the need of protection . 225.5 Procedure to evaluate the cost effectiveness of protection 235.6 Protection measur
27、es . 265.7 Selection of protection measures 266 Assessment of risk components . 266.1 Basic equation 266.2 Assessment of risk components due to flashes to the structure (S1) . 276.3 Assessment of the risk component due to flashes near the structure (S2) . 276.4 Assessment of risk components due to f
28、lashes to a line connected to the structure (S3) 276.5 Assessment of risk component due to flashes near a line connected to the structure (S4) 286.6 Summary of risk components 296.7 Partitioning of a structure in zones ZS296.8 Partitioning of a line into sections SL306.9 Assessment of risk component
29、s in a structure with zones ZS306.10 Cost-benefit analysis for economic loss (L4) . 31Annex A (informative) Assessment of annual number N of dangerous events 32A.1 General . 32A.2 Assessment of the average annual number of dangerous events NDdue to flashes to a structure and NDJto an adjacent struct
30、ure 32A.3 Assessment of the average annual number of dangerous events NMdue to flashes near a structure 37A.4 Assessment of the average annual number of dangerous events NLdue to flashes to a line. 38A.5 Assessment of average annual number of dangerous events NIdue to flashes near a line. 39Annex B
31、(informative) Assessment of probability PXof damage 40B.1 General . 40B.2 Probability PAthat a flash to a structure will cause injury to living beings by electric shock 40B.3 Probability PBthat a flash to a structure will cause physical damage 41BS EN 62305-2:2012EN 62305-2:2012 2 3 EN 62305-2:2012
32、B.4 Probability PC that a flash to a structure will cause failure of internal systems 41B.5 Probability PM that a flash near a structure will cause failure of internal systems 43B.6 Probability PU that a flash to a line will cause injury to living beings by electric shock 44B.7 Probability PVthat a
33、flash to a line will cause physical damage 45B.8 Probability PW that a flash to a line will cause failure of internal systems . 46B.9 Probability PZthat a lightning flash near an incoming line will cause failure of internal systems 46Annex C (informative) Assessment of amount of loss LX. 48C.1 Gener
34、al . 48C.2 Mean relative amount of loss per dangerous event . 48C.3 Loss of human life (L1) . 48C.4 Unacceptable loss of service to the public (L2) . 51C.5 Loss of irreplaceable cultural heritage (L3) . 52C.6 Economic loss (L4) . 53Annex D (informative) Evaluation of costs of loss 56Annex E (informa
35、tive) Case study . 57E.1 General . 57E.2 Country house 57E.3 Office building . 62E.4 Hospital 69E.5 Apartment block 80Bibliography . 85Figures Figure 1 Procedure for deciding the need of protection and for selecting protection measures . 24Figure 2 Procedure for evaluating the cost-effectiveness of
36、protection measures 25Figure A.1 Collection area ADof an isolated structure . 33Figure A.2 Complex shaped structure 34Figure A.3 Different methods to determine the collection area for the given structure 35Figure A.4 Structure to be considered for evaluation of collection area AD36Figure A.5 Collect
37、ion areas (AD, AM, AI, AL) . 39Figure E.1 Country house 57Figure E.2 Office building 62Figure E.3 Hospital 69Figure E.4 Apartment block . 81Tables Table 1 Sources of damage, types of damage and types of loss according to the point of strike 18Table 2 Risk components to be considered for each type of
38、 loss in a structure 20Table 3 Factors influencing the risk components . 21Table 4 Typical values of tolerable risk RT22Table 5 Parameters relevant to the assessment of risk components 28Table 6 Risk components for different types of damage and source of damage . 29Table A.1 Structure location facto
39、r CD. 37Table A.2 Line installation factor CI. 38BS EN 62305-2:2012EN 62305-2:2012 3 EN 62305-2:2012 4 Table A.3 Line type factor CT38Table A.4 Line environmental factor CE. 38Table B.1 Values of probability PTAthat a flash to a structure will cause shock to living beings due to dangerous touch and
40、step voltages 40Table B.2 Values of probability PBdepending on the protection measures to reduce physical damage 41Table B.3 Value of the probability PSPD as a function of LPL for which SPDs are designed42Table B.4 Values of factors CLDand CLI depending on shielding, grounding and isolation conditio
41、ns . 42Table B.5 Value of factor KS3 depending on internal wiring . 44Table B.6 Values of probability PTUthat a flash to an entering line will cause shock to living beings due to dangerous touch voltages 45Table B.7 Value of the probability PEBas a function of LPL for which SPDs are designed 45Table
42、 B.8 Values of the probability PLDdepending on the resistance RS of the cable screen and the impulse withstand voltage UW of the equipment . 45Table B.9 Values of the probability PLI depending on the line type and the impulse withstand voltage UWof the equipment 47Table C.1 Type of loss L1: Loss val
43、ues for each zone . 49Table C.2 Type of loss L1: Typical mean values of LT, LF and LO. 49Table C.3 Reduction factor rtas a function of the type of surface of soil or floor 50Table C.4 Reduction factor rpas a function of provisions taken to reduce the consequences of fire 50Table C.5 Reduction factor
44、 rf as a function of risk of fire or explosion of structure . 51Table C.6 Factor hzincreasing the relative amount of loss in presence of a special hazard51Table C.7 Type of loss L2: Loss values for each zone . 52Table C.8 Type of loss L2: Typical mean values of LF and LO. 52Table C.9 Type of loss L3
45、: Loss values for each zone . 52Table C.10 Type of loss L3: Typical mean value of LF. 53Table C.11 Type of loss L4: Loss values for each zone . 53Table C.12 Type of loss L4: Typical mean values of LT,LF and LO. 54Table C.Z1 Values to assess the total value ct. 54Table C.Z2 Portions to assess the tot
46、al values ca, cb, cc, cs. 55Table E.1 Country house: Environment and structure characteristics . 58Table E.2 Country house: Power line . 58Table E.3 Country house: Telecom line (TLC) . 59Table E.4 Country house: Factors valid for zone Z2(inside the building) . 60Table E.5 Country house: Collection a
47、reas of structure and lines 60Table E.6 Country house: Expected annual number of dangerous events 61Table E.7 Country house: Risk R1for the unprotected structure (values 105) . 61Table E.8 Country house: Risk components relevant to risk R1 for protected structure 62Table E.9 Office building: Environ
48、ment and structure characteristics . 63Table E.10 Office building: Power line . 63Table E.11 Office building: Telecom line 64Table E.12 Office building: Distribution of persons into zones 64Table E.13 Office building: Factors valid for zone Z1(entrance area outside) 65Table E.14 Office building: Factors valid for zone Z2(garden outside) 65BS EN 62305-2:2012EN 62305-2:2012 4 5 EN 62305
