Here are some common misconceptions and questions about lightning and
lightning protection:
-
Lightning never strikes
twice.
The Empire State Building is struck over two dozen times a year. Your building
will certainly not be struck as often, but statistics show that if lightning
has struck a building once, the chances of it getting struck again are much
higher than for a building that has never been struck.
-
If I put lightning rods
on my house, they will attract lightning.
Lightning rods do not have an impact on whether a building will be struck by
lightning. They are designed to intercept and conduct a bolt of lightning to ground
that has already zeroed in on the structure because of other conditions.
-
I have lots of tall trees
around my house, so I don't need lightning protection.
Trees do not provide protection from lightning because of the dangerous
ground charge that accompanies the stroke and travels through surrounding
buildings.
-
My TV antenna acts as a
lightning rod, so I'm already protected.
Your television antenna is a target that does not have adequate grounding
to safely conduct a lightning bolt to ground.
-
My lightning surge
suppressors and voltage spike protectors are all the protection I need from
lightning damage.
Such devices are an integral part of a complete lightning protection system,
but used alone will not protect a structure from lightning damage.
-
My building is safe
because it is in a low lying area.
Lightning frequently strikes in low lying areas as well as in higher
locales.
-
Lightning rods will make
my building look unattractive.
An experienced installation contractor can tailor a lightning
protection system to aesthetically blend in with any surroundings. In many
cases it can be hidden entirely, except for the air terminals themselves.
-
Modern inventions such as
"dissipation arrays" can prevent lightning from striking a building.
Lightning is a tremendously powerful, uncontrollable force that will strike
when and where conditions are right, much like a hurricane or tornado.
Think of lightning protection like a storm cellar - it protects you
(and your property) but cannot stop the event from occurring.
-
New designs in lightning
rods provide enhanced protection compared to conventional "Franklin rod"
systems.
The overwhelming majority of the international academic community has found
the claims of these devices to be without merit. In 2003, US District Court in
Arizona ruled that two sellers of these devices engaged in false advertising
by claiming that their "Early Streamer Emission" (ESE) lightning rods provide a significantly expanded,
measurable zone of protection without having any reasonable scientific basis
for making such a claim. Follow this link for more information.
-
Lightning protection
system cables get very hot when they carry a strike, so they must be kept away
from any flammable material, such as insulation.
Electrical wiring gets hot when there is resistance, like the coil on a stove.
Because a lightning rod system is well grounded, there is virtually no
resistance and the cable has no time to heat up. Lightning rod cable can
safely be concealed in a house surrounded by insulation and attached to wooden
structural members.
-
Do lightning protection
systems require
routine maintenance?
No. Due to the composition of lightning protection components, no maintenance
is required unless changes are made to the structure or the system is
disturbed.
-
Are lightning protection
systems
expensive?
No. Typically, the cost of a lightning protection system is less than 1% of the total cost
of the structure.
