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3.1 Necessity of a lightning protection For the following reasons: According to article 15, section 7
system – Legal regulations of the Bavarian building regulations (valid section at the time
of the court decision), structures where a lightning strike can
The purpose of a lightning protection system is to protect easily occur or can have serious consequences due to their
buildings from direct lightning strikes and possible fire or from location, type of construction or use must be equipped with
the consequences of lightning currents (non-igniting flash). permanently effective lightning protection systems. Thus, ef-
If national regulations such as building regulations, special fective protective devices are required in two cases. In the first
regulations or special directives require lightning protection case, the structures are particularly susceptible to lightning
measures, they must be implemented. strikes (e.g. due to their height or location); in the other case, a
If these regulations do not specify a class of LPS, a lightning lightning strike (e.g. due to the type of construction or use) can
have particularly serious consequences. The plaintiff´s build-
protection system which meets the requirements of class of ing falls under the latter category since it is used as a nursery
LPS III according to IEC 62305-3 (EN 62305-3) is recommended school. A nursery school is a structure where a lightning strike
as a minimum. In principle, a risk analysis, which is described can have serious consequences due to its use. The fact that
in the IEC 62305-2 (EN 62305-2) standard (see chapter 3.2.1), nursery schools are not expressly mentioned in the examples
should be performed for an overall assessment. of structures which are particularly at risk in the notes of the
Bavarian building regulations does not make any difference.
In Germany, the The risk of serious consequences if lightning hits a nursery
¨ VdS 2010 guideline “Risikoorientierter Blitz- und Über- school results from the fact that, during day time, a large num-
spannungsschutz, Richtlinien zur Schadenverhütung” ber of children under school age are present at the same time.
[“Risk-oriented lightning and surge protection, guideline The fact that the rooms where the children spend their time are
for damage prevention”] on the ground floor and that the children could escape through
several windows – as put forward by the plaintiff – is not deci-
can be used to determine the class of LPS. sive. In the event of fire, there is no guarantee that children of
this age will react sensibly and leave the building through the
For example, the Bavarian building regulations (BayBO) state windows, if necessary. In addition, the installation of sufficient
that permanently effective lightning protection systems must lightning protection equipment is not too much to expect of
be installed when lightning can easily strike a structure or can the operator of a nursery school. Article 36, section 6 of the
have serious consequences due to: Bavarian building regulations (valid section at the time of the
court decision) requires that, amongst other things, staircases
¨ Its location,
must have entrances to the basement which have self-closing
¨ Its type of construction or doors which are, at least, fire-retardant. This requirement does
¨ Its use not apply to residential buildings with up to two flats (arti-
This means: A lightning protection system must be in- cle 36, section 10 of the Bavarian building regulations (valid
stalled even if only one of the requirements is met. section at the time of the court decision)). The defendant only
made the demand when the plaintiff converted the building,
A lightning strike can have particularly serious conse- which was previously used as a residential building, into a
quences for structures due to their location, type of construc- nursery school in accordance with the authorised change of
tion or use. use. The exemption provision of article 36, section 10 of the
A nursery school, for example, is a structure where a lightning Bavarian building regulations (valid section at the time of the
strike can have serious consequences due to its use. court decision) cannot be applied to buildings which were built
The interpretation of this statement is made clear in the fol- as residential buildings with up to two flats, but which now
lowing court judgement: (also) serve another purpose which justifies the application
Extract from the Bavarian Administrative Court, decision of of the safety requirements in article 36, section 1 to 6 of the
4 July 1984 – No. 2 B 84 A.624. Bavarian building regulations (valid section at the time of the
1. A nursery school is subject to the requirement to install ef- court decision). This is the case here.
fective lightning protection systems.
Serious consequences (panic) can also arise when lightning
2. The legal requirements of the building regulations for at hits places of public assembly, schools and hospitals. For
least fire-retardant doors when designing staircases and these reasons, it is necessary that all endangered structures
exits also apply to a residential building which houses a are equipped with permanently effective lightning protection
nursery school. systems.

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