 
Lightning
Safety For Campers, Hikers, & Backpackers
By: Richard
Kithil, President - National
Lightning Safety Institute
Some
unexpected situations present extreme danger - an angry
fer-de-lance, a Class VI rapid, crumbling cornices and rotten
rock - these can be perilous events. There is no defense
for lightning's "bolt-out-of-the-blue" occasional
strike. But for the most part, lightning safety is a risk
management procedure. Early recognition of the lightning
hazard, with an awareness of defensive options, will provide
high levels of safety.
Common
Misconceptions And Myths
1.
Lightning
never strikes twice…
it strikes the Empire State Building in NYC some 22-25
times per year !
2. Rubber
tires or a foam pad will insulate me from lightning…
it takes about 10,000 volts to create a one inch spark.
Lightning has millions of volts and easily can jump
10-20 feet !
3. Lightning
rods will protect my ropes course…lightning
rods are "preferential attachment points"
for lightning. You do not want to "draw"
lightning to any area with people nearby.
4. We should
get off the water when boating, canoeing or sailing…tall
trees and rocky outcrops along shore and on nearby
land may be a more dangerous place.
5. A cave
is a safe place in a thunderstorm…if it
is shallow cave, or an old mine with metallics nearby,
it can be a deadly location during lightning.
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 Atmospheric
Physics 101:
At any one time around the planet, there are 2000 thunderstorms
and 100 lightning strikes to earth per second. The frequency
of lightning increases in the lower latitudes (closer to
the equator), and in the higher altitudes (mountainous terrain).
In the USA, central Florida experiences some 10-15 lightning
strikes per sq. km./yr. The Rocky Mountain west has about
two thirds this activity. Central Africa, parts of Southeast
Asia, and the Latin American mountain regions can experience
two to three times as much lightning as central Florida.
Lightning leaders
from thunderclouds proceed in steps of tens of meters, electrifying
ground-based objects as they approach the earth. Ground-based
objects may launch lightning streamers to meet these leaders.
Streamers may be heard (some say they "sound like bacon
frying") and seen (we may notice our hair standing
on end). A connecting leader-streamer results in a closed
circuit cloud-to-ground lightning flash. Thunder accompanying
it is the acoustic shock wave from the electrical discharge.
Thus, thunder and lightning are associated with one another.
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Flash/Bang:
We all possess a first-class lightning detection device, built
into our heads as standard equipment. By referencing the time
in seconds from seeing the lightning (the FLASH, or "F"
) to hearing the accompanying thunder (the BANG, or "B"),
we can range lightning's distance. A "F" to "B"
of five seconds equals lightning distance being one mile away.
A "F" to "B" of ten = two miles; a "F"
to "B" of twenty = four miles; a "F" to
"B" of thirty = six miles; etc. New
information shows successive, sequential lightning strikes
(distances from Strike 1 to Strike 2 to Strike 3) can be
some 6-8 miles apart. Taking immediate defensive actions
is recommended when lightning is indicated within 6-8 miles.
The next strike could be close enough to be an immediate
and severe threat.
Lightning is
a capricious and random event. It cannot be predicted with
any accuracy. It cannot be prevented. Advanced planning
in the form of a risk management program is the best defense
for maximum safety.
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For
more information please refer to the