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Figure 7.3.7a Galvanised reinforcement mats for shielding the Figure 7.3.7b Use of galvanised reinforcement mats for shielding,
building e.g. in case of planted roofs
strength is indirectly proportional to the distance s a . The mag- tection zones. A meshed interconnection creates an effective
nitude of the magnetic field inside a volume to be protected electromagnetic shield.
e.g. LPZ 1 (Figure 7.3.5) can be described by the shielding Figure 7.3.6 shows the principle of how a steel reinforcement
quality. can be developed into an electromagnetic cage (hole shield).
In practice, however, it is not possible to weld or stick together
Implementation of the magnetic shield attenuation every junction in large structures. The usual practice is to install
of building / room shields a meshed system of conductors into the reinforcement, said
Extended metal components such as metal roofs and façades, system typically having a size of a ≤ 5 m. This meshed network
steel reinforcements in concrete, expanded metals in walls, is connected in an electrically safe way at the cross points, e.g.
grids, metal supporting structures and pipe systems existing in by means of clamps. The reinforcement is “electrically hitched”
the building are particularly important when shielding against onto the meshed network at a typical distance of b ≤ 1 m. This
magnetic fields and thus for the installation of lightning pro- is done on site, for example by means of tie connections.

concrete earthing ring conductor
façade
concrete support flat strip holder

steel support

fixed earthing terminal

floor slab

Figure 7.3.8 Shielding of a building

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