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Petrol stations are highly vulnerable to lightning strikes and Equipment located in the forecourt (e.g. petrol price display)
surges due to their extremely sensitive control and display and the incoming utility line are vulnerable to direct lightning
systems. strikes. Therefore, lightning current arresters are installed at
In Germany, the necessity of a lightning protection system for the entrance point into the building.
petrol stations must be determined amongst others based on a The fuel dispensers are located underneath a projecting metal
risk analysis according to the German Ordinance on Industrial roof and are thus protected against direct lightning strikes.
Safety and Health (BetrSichV), the German technical rules for For this reason and due to the intermeshed earth-termination
operating safety (TRBS 2152 Part 3), VDE standards and fire system (Figure 9.21.1), surge arresters are installed at the
protection requirements of the relevant building regulations. entrance point of the lines into the petrol station building and
The German Ordinance on Industrial Safety and Health at the entrance point of the lines into the fuel dispenser to
(BetrSichV) requires to avoid all sources of ignition. Some protect the lines leading to the fuel dispenser electronics.
building regulations specify that structures where a lightning
strike can easily occur or can have serious consequences due A professional external lightning protection system as per
to their location, type of construction or use must be equipped IEC 62305 (EN 62305), consistent lightning equipotential
with permanently effective lightning protection systems. bonding and additional surge protection measures are re-
quired to protect petrol stations from direct lightning strikes.
The risk analysis described in the IEC 62305-2 (EN 62305-2) The table in Figure 9.21.1 shows which types of surge protec-
lightning protection standard can be used to determine pos- tive devices can be used to protect the different interfaces and
sible risks. The system-specific parameters define the existing system components.
risk of a structure. If the risk values determined are higher than It is important to interconnect all metal constructions (e.g.
the tolerable risks listed in the standard, measures (external pipes, fuel dispenser enclosures, tanks) and to connect them
lightning protection, surge protection, fire alarm systems, etc.) to the earth-termination system of the petrol station building.
must be taken which reduce the inadmissibly high risks to an According to IEC 62305-3 (EN 62305-3), the earth-termination
acceptable level. system should have an earth resistance of < 10 Ω (recommen-
The IEC 60364-1 (HD 60364-1) standard specifies that “prop- dation). Spark gaps for use in hazardous areas must be used to
erty shall be protected against damage as a consequence of connect petrol stations with cathodic corrosion protection to
overvoltages such as those originating from atmospheric the earth-termination system.
events or from switching”.
The surge protective devices recommended in this standard The bus systems, sensors and information technology connec-
must not be installed in Ex zones (zone 0, 1 and 2), if any. tions listed in Figure 9.21.1 are by no means complete and
If surge protective devices are located in hazardous zones, merely serve as examples. They may only be installed based
adequate measures (e.g. approved enclosures and / or ap- on the information provided in the detailed planning and the
proved surge protective devices) must be taken to avoid requirements and notes of the acceptance body.
ignition.

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