Issue 44 winter 24 - Journal - Page 74
Lightning protection
Lightning Protection UK Limited are an independent company, specialising in the design, supply
and installation of lightning protection and specialist low resistance earthing systems.
It is essential that Lightning Protection Systems be
designed, installed and maintained by trained and
competent engineers. All of our Lightning Protection UK
operatives are CSCS card holders.
out plaster walls and crack foundations. Shrapnel is a
common secondary damaging effect.
Power surge damage - If lightning chooses any of the
buildings electrical wiring as its primary or secondary
route, the explosive surge can damage anything, even non
electrical appliances that are connected. Even if most of
the lightning current takes another path to the ground,
the buildings electrical system will experience enough of
a surge to probably cause significant damage to anything
connected to it. Mostly anything electrical receiving most
of the damage.
A Lightning Protection System (LPS) is put into place to
prevent or lessen lightning strike damage to buildings and
property. Lightning can strike the same structure time and
time again, which is why it is essential to have a Lightning
Protection System installed.
A Risk Assessment could be needed in some instances
and we do offer this service. Once you have established
the need for a Lightning Protection System, a system will
then need to be designed specifically for the structure it
is required for.
A professionally installed and well maintained lightning
protection system will certainly reduce and potential to
eliminate fire and injury hazards to a building and the
public in it.
Quite often, very tall structures/areas such as mountains,
tower blocks (flats) and radio towers are more likely to be
struck because of the narrow gap between the charge separation of the ground below and the charge cloud above.
Lightning is formed to balance a charge separation; positive and negative. When the charge builds up enough to
overcome the resistance of the air, the opposite charge
will race upwards along the structure more easily, then
through the air. As a result the gap between the 2 charges
is lessened, this creating an increased chance of a strike.
Lightning also presents hazards to smaller structures such
as houses, small factories, offices, schools, churches and
many more.
It is recommended that a Lightning Protection system be
maintained properly and tested and inspected on an annual basis, we like other specialist LP Companies, do recommend 11 monthly testing, this then ensures that all
weather conditions and seasonal change are taken into
consideration.
Three of the main hazards of a direct lightning strike are:
Fire Damage - The biggest danger lightning poses to
these types of buildings is fire. Wood and other flammable
building materials can be very easily ignited, where an exposed lightning channel comes into contact with or passes
through them. It is most common for lightning to start a
fire in the roof of a property or building, as the channel
quite often has to pass through some of the structural material in a roof before it can reach a more conductive path
such as wiring or pipe work. When a lightning current
passes through cables or wires, it will most likely cause a
fire, this could happen anywhere along the affected
circuits.
Shockwave damage - Another significant source of
damage from lightning comes through the explosive
shockwave. The shockwaves that lightning create is what
produces the thunder sound that we hear. At close range
these shockwaves can be very destructive. Lightning can
easily break or fracture brick, stone or concrete. Chimneys
are one of the more common areas of a building severely
damaged by lightning. Shockwaves caused by lightning
can quite easily create trenches in soil, shatter glass, blow
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Conservation & Heritage Journal
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