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Section 4.8
Lightning Safety for Campers and Hikers
By Richard Kithil, President & CEO, NLSI
Article published in The Outdoor Network, vol ix, no.2, 1998
1.0 Summary. 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.
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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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2.0 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.
3.0 Standard lightning defenses. The eco-tourism environment is
different from situations where substantial buildings or fully enclosed
metal vehicles are the recommended shelters. Lightning in remote terrain
creates dangerous conditions. Follow these guidelines:
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LIGHTNING SAFETY TIPS
AVOID: Avoid water. Avoid all metallic objects. Avoid
the high ground. Avoid solitary tall trees. Avoid close contact
with others - spread out 15-20 ft. apart. Avoid contact with dissimilar
objects (water & land; boat & land; rock & ground;
tree & ground). Avoid open spaces.
SEEK: Seek clumps of shrubs
or trees of uniform height. Seek ditches, trenches or the low
ground. Seek a low, crouching position with feet together with
hands on ears to minimize acoujstic shock from thunder.
KEEP: Keep a high level of safety awareness for thirty
minutes after the last observed lightning or thunder.
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4.0 Medical treatment and symptoms. Treat the apparently dead first.
Immediately administer CPR to restore breathing. Eighty percent of lightning
strike victims survive the shock. Lightning strike victims do not retain
an electric charge and are safe to handle. Common lightning aftereffects
include impaired eyesight and loss of hearing. Electrical burns should
be treated as other burns.
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Treat lightning like a snake: if you
see it or hear it, take evasive measures.
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