With regard the risk ignition dangerous, po-
tentially explosive atmosphere through lightning
strike, the Technical Rules for Hazardous Substances
No. 509 refer TRBS 2152 Part Number 5.
This also applies above-ground tanks the open
air and underground tanks with flammable liquids with
an ignition point °C, which are not completely
surrounded earth, masonry, concrete multiples
of these substances. Starting the light-
ning strike point, strong currents flow, which can
cause sparks close the impact point. Ap-
pendix the TRGS lists individual details the
use and requirements spark gaps pipe lines, as
well detailed requirements lightning and surge
protection units according IEC/EN 62305. Building
sections containing tanks store flammable liquids
with ignition point and volume more
than 3,000 litres must protected against ignition
risks from lightning strikes using suitable equipment.8. Even without
a direct lightning strike, induced voltages can cause
damage electrical devices, systems and compon-
ents for measurement, control and regulation (MCR)
technology and, the worst case, can lead ex-
plosion. The strong heating the arresting paths the
lightning can also trigger ignition.1127-1 states, lightning strikes potentially ex-
plosive atmosphere, then the atmosphere always ig-
nited.
For this reason, the three basic principles explo-
sion protection are:
• Avoid potentially explosive atmospheres
• Avoid any possibly effective source ignition
• Limit possible explosion impacts reasonable
level
Special requirements for lighting and surge protec-
tion areas
The lightning protection measures must created in
such way that there are melting and spray im-
pacts.
For this reason, when planning and running lightning
protection system through potentially explosive areas
– so-called zones the following rules must addi-
tionally taken into account:
• IEC/EN 62305-3 Appendix D
"Additional information for lightning protection sys-
tems for structure potentially explosive areas"
• VDE 0185-305-3 Supplement 2
"Additional information for special building struc-
tures"
In systems with zone and zone 22, Ex
atmosphere will most likely only occur rare, unfore-
seen circumstances. lightning protection system erected accord-
ing IEC/EN 62305-3, the creation ignitable
sparks, well interfering damaging impacts on
electrical systems through the impact lightning,
need not prevented every case. Therefore, possible posi-
tion air-termination systems zone and zone
22, taking Appendix IEC/EN 62305-3 into ac-
count.
TBS
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Chapter The external lightning protection system
