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rod is to intercept lightning and to safely conduct it to the If the shelter has a minimum height of about 3 m, the safety
ground to prevent dangerous sparking, thus protecting the distance from the rooftop lightning rod (air-termination con-
structure from fire and mechanical destruction. The formation ductor or rod) is maintained. However, it is more difficult to
of a high lightning voltage in the ground, also referred to as keep an adequate distance from the outer walls. Therefore,
potential gradient area, endangers persons in the shelter. This the wall / wall construction where the lightning rod (down
life-threatening voltage may flow into the feet of a person conductor wire) is led to the ground must have an adequate
standing on the ground. It is therefore also referred to as step wall thickness (Figure 9.28.2). To connect the lightning rod to
voltage. Moreover, persons must maintain an adequate safety the ground, earth rods (metal rods of a defined length, mate-
distance from the lightning rod to prevent dangerous touch rial suitable for the local conditions) are commonly used. On
voltages (Figure 9.28.1). each down conductor, the earth rods are vertically buried in
Effective lightning protection measures that protect golfers, the ground at a depth of about 6 m to 9 m depending on the
hikers, etc. from lightning interference can be taken for shelters type of ground (Figures 9.28.2 to 9.28.5).
with a relatively low effort. In addition to technical measures, Log-structured shelters usually have the above mentioned wall
thickness. However, the situation is quite different when it
it is equally important that golfers know what to do during a comes to shelters with thin wood walls. In this case, the down
thunderstorm. In an upcoming thunderstorm, they should seek conductors must be installed directly at the outer edges near
shelter immediately and stay there until the thunderstorm has the wall construction to ensure the maximum wall thickness
disappeared. (Figure 9.28.2). As an alternative, an isolated lightning pro-
The following considerations are based on commonly used tection system* can be used.
wood shelters. (* Extensive expert knowledge is required. For this reason,
please contact a certified lightning protection specialist (for
Prevention of touch voltages example, in Germany VDE-certified (Verband der Elektrotech-
To prevent dangerous high touch voltages, an adequate safety nik Elektronik Informationstechnik) or VDB-certified (Verband
distance must be maintained between the lightning rod and Deutscher Blitzschutzfirmen e.V.) lightning protection experts).
the persons in the shelter. In a shelter of about 3 m x 3 m with Another possibility to maintain the safety distance required to
an eaves height of 3 m and the lightning rod shown in Figure protect shelters in case of a lightning strike is to use highly
9.28.2, 10 cm wooden beams are required. insulating lightning rods, for example CUI Conductors from

down conductor
at least
10 cm

down
conductor
beam

potential
control

earth rod

equipotential bonding conductor

Figure 9.28.2 Installation of a down conductor at the side beams to ensure that the separation distance is maintained

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