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While it is difficult to quantify lightning losses, it is estimated that $4-5
billion damage occurs each year. Likewise, the cost of lightning protection to safeguard
critical equipment and facilities from lightning strikes during severe weather is
enormous.
Lightning - the most dangerous and most frequently encountered weather hazard
most people experience each year - is the second most frequent weather-related killer
in the United States. About 100 people lose their lives and more than 500 are injured
by lightning every year. Most casualties result from inappropriate behavior during
thunderstorms, particularly when people are caught outdoors during recreation or
organized sports. Being aware of - and following - proven lightning safety guidelines
can greatly reduce the risk of injury or death. -
NOAA National
Severe Storms Lab
Excerpt from the NOAA
National Severe Storms Laboratory...
What does lightning do to people?
Cloud-to-ground lightning can kill and injure people by direct or indirect means.
It is not known if all people are killed who are directly struck by the flash itself.
The lightning current can branch off to a person from a tree, fence, pole, or other
tall object. In addition, flashes may conduct their current through the ground to
a person after the flash strikes a nearby tree, antenna, or other tall object. The
current also may travel through power or telephone lines to a person who is in contact
with electric appliances, tools, electronics, or a corded telephone. Lightning can
also travel through plumbing pipes and water to a person in contact either with
a plumbing fixture or a person in water, including bathtubs, pools, and the running
water of a shower.
Damage to the human body:
Lightning affects the many electrochemical systems in the body. People struck
by lightning can suffer from nerve damage, memory loss, personality change, and
emotional problems. There is a national support group for lightning and electric
shock survivors.
An example is some single nerve cells, such as those extending from the brain
to the foot, can be as long as 6 feet or more. These types of cells are most prone
to lightning damage due to the instantaneous potential difference across the length
of the cell as lightning begins to enter the body.
The intense heat of the lightning stroke can turn sweat instantly to steam and
the tremendous pressure of the steam has been known to blow people's boots, shoes,
and clothing off them. In places where metal is in contact with or close proximity
to the body, such as jewelry or belt buckles, burn marks are found. Likewise, burn
marks are found in places where the body had been sweaty, such as the feet, underarms,
and chest.
How to stay safe when lightning is around - "If you can hear it, fear it!"
The best defense is plan ahead and avoid exposure to lightning when a thunderstorm
occurs. Know where safe shelter is located and leave enough time to reach safe shelter
before your danger level is high. Don't be an isolated tall object, and don't be
connected to anything that may be an isolated tall object.
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USE THE 30-30 RULE!
- 30 seconds flash-to-bang - time to take shelter!
- 30 minutes after the last thunder is heard - safe to resume activities.
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