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This standard is a guideline on how to prevent explosions and is often far greater than the physical damage to the hardware
to protect against the effects of explosions by taking measures of the installation affected.
during the design and installation of devices, protection sys- The aim of a risk analysis is to objectify and quantify the risk
tems and components. to structures and their contents as a result of direct and indi-
Section 5.7 and 6.4.8 require protection against the effects of rect lightning strikes. This new way of thinking is embodied in
a lightning strike if the installations are at risk. the international standard IEC 62305-2:2006 or the European
standard EN 62305-2:2006 which has been revised in 2010.
IEC 60079-14:2007 (EN 60079-14:2008) The risk analysis presented in IEC 62305-2 (EN 62305-2) en-
Electrical installations design, selection and erection sures that it is possible to draw up a lightning protection con-
It is pointed out that the effects of lightning strikes must be cept which is understood by all parties involved and which
observed. The standard requires comprehensive equipotential meets optimum technical and economic requirements, which
bonding in all Ex zones.
means that the necessary protection can be ensured with as
little expenditure as possible. A detailed description of the
VDE series 65
Elektrischer Explosionsschutz nach DIN VDE 0165; VDE Ver- protection measures resulting from the risk analysis can be
lag Berlin, Anhang 9: PTB-Merkblatt für den Blitzschutz an found in Part 3 and 4 of the IEC 62305 (EN 62305) standard
eigensicheren Stromkreisen, die in Behälter mit brennbaren series.
Flüssigkeiten eingeführt sind [Electrical explosion protection
according to DIN VDE 0165, Annex 9: PTB bulletin for protect-
ing intrinsically safe circuits installed in tanks with flammable 3.2.1 Sources of damage, types of damage
liquids against lightning strikes] and types of loss
The actual sources of damage are lightning strikes that are
subdivided into four groups depending on the point of strike
In Germany, standards can be obtained from:
(Table 3.2.1.1):
VDE VERLAG GMBH or: Beuth-Verlag GmbH S1 Direct lightning strike to a structure;
Bismarckstr. 33 Burggrafenstr. 6 S2 Lightning strike near a structure;
10625 Berlin 10787 Berlin
Germany Germany S3 Direct lightning strike to an incoming line;
Phone: +49 30 34 80 01-0 Phone: +49 30 2601-0
Fax: +49 30 341 70 93 Fax: +49 30 2601-1260 S4 Lightning strike near an incoming line.
eMail: [email protected] Internet: www. beuth.de These sources of damage may result in different types of
Internet: www.vde-verlag.de
damage which cause the loss. The standard specifies three
types of damage:
3.2 Explanatory notes on the D1 Injury to living beings by electric shock as a result of
touch and step voltage;
IEC 62305-2 (EN 62305-2) standard:
Risk management D2 Fire, explosion, mechanical and chemical reactions
as a result of the physical effects of the lightning dis-
Risk management with foresight includes calculating the risks charge;
for a company. It provides the basis for taking decisions on D3 Failure of electrical and electronic systems as a result
how to limit these risks and it makes clear which risks should of surges.
be covered by insurance. However, it should be borne in mind
that insurance is not always a suitable means of achieving
certain aims (e.g. maintaining the ability to deliver). The prob- Depending on the type of construction, use and substance
abilities that certain risks will occur cannot be changed by in- of the structure, the relevant loss can be very different.
surance. IEC 62305-2 (EN 62305-2) specifies the following four types
Manufacturing companies using extensive electronic installa- of loss:
tions or companies providing services (and nowadays this ap- L1 Loss of human life (injury to or death of persons);
plies to most companies) must also give special consideration L2 Loss of service to the public;
to the risk presented by lightning strikes. It must be observed
that the damage caused by the non-availability of electronic L3 Loss of cultural heritage;
installations, production and services, and also the loss of data, L4 Loss of economic value.

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