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as induced voltages and currents caused by direct and indirect liability only exists, however, if the work was already faulty at
lightning strikes. the time of acceptance! Circumstances occurring subsequently
The importance and necessity of this standard derive from the – such as a further development of the state of the art – do
increasing use of different electrical and electronic systems, not belatedly make the previously accepted, defect-free work
which are referred to as information systems. To protect these faulty!
information systems, the structure is divided into lightning pro- For the question of the deficiency of work and service, the state
tection zones (LPZs). This allows to consider local differences of the recognised engineering rules at the time of the accept-
in number, type and sensitivity of the electrical and electronic ance is the sole deciding factor.
devices when choosing the protection measures. For each Since, in the future, only the new lightning protection stand-
lightning protection zone, a risk analysis in accordance with ards will be relevant at the time of completion and acceptance
IEC 62305-2 (EN 62305-2) is performed to select those protec- of lightning protection systems, they have to be installed in
tion measures which provide optimum protection at minimum accordance with these standards. It is not sufficient that the
cost. service conformed to the engineering rules at the time it was
provided, if, between completion of a contract, service provi-
The IEC 62305 (EN 62305) standards Parts 1 to 4 can be used sion and acceptance of the construction work, the technical
to design, install, inspect and maintain lightning protection knowledge and hence the engineering rules have changed.
systems for structures, their installations, their contents and Thus, works which have been previously installed and already
the persons within.
accepted under the old standards do not become defective be-
cause, as a result of the updating of the standards, a “higher
technical standard” is demanded.
1.2 Work contracts With the exception of lightning protection systems for nuclear
A work contractor is fundamentally liable for ensuring that his facilities, lightning protection systems have only to conform
service is free of deficiencies. Compliance with the recognised to the state of the art at the time they are installed, i.e. they
engineering rules is the decisive starting point for work and do not have to be updated to the latest state of the art. Exist-
service free of deficiencies. Relevant national standards are ing systems are inspected in the course of maintenance tests
used here in order to fill the factual characteristic of the “rec- according to the standards in force at the time they were in-
ognised engineering rules” with life. If the relevant standards stalled.
are complied with, it is presumed that the work and service is
free of deficiencies. The practical significance of such a prima
facie evidence lies in the fact that a customer who lodges a 1.3 Product standards
complaint of non-conform service by the work contractor (for
example for the installation of a lightning protection system) Materials and components for lightning protection systems
has basically little chance of success if the work contractor can must be designed and tested for the electrical, mechanical and
show that he complied with the relevant technical standards. chemical stress (e.g. corrosion) which has to be expected dur-
As far as this effect is concerned, standards and preliminary ing use. This affects both the components of the external and
standards carry equal weight. The effect of the presumption of internal lightning protection system.
technical standards is removed, however, if either the stand-
ards are withdrawn, or it is proven that the actual standards no IEC 62561-1 (EN 62561-1): Lightning protection
longer represent the state of the art. Standards cannot stati- system components (LPSC) – Requirements for
cally lay down the state of the recognised engineering rules in connection components
tablets of stone as technical requirements and possibilities are This standard describes test procedures for metal connec-
continually changing. If standards are withdrawn and replaced tion components. Components falling within the scope of this
with new standards or preliminary standards, it is primarily standard are:
the new standards which correspond to the state of the art.
National supplements reflect the recognised state of the art. ¨ Clamps
Contractors and those placing an order for work regularly ¨ Connectors
agree that the work must conform to the general state of the ¨ Connection components
art without the need to make specific mention of this. If the ¨ Bridging components
work shows a negative deviation from this general state of the
art, it is faulty. This can result in a claim being made against ¨ Expansion pieces
the contractor for material defect liability. The material defect ¨ Test joints

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