2004-7-20
This is Phoebe Zimmermann with the VOA Special English Health
Report.
People who are hit by lightning and survive often have long-term
effects. These may include memory loss, sleep disorders, muscle pain
and depression.
Experts tell people to seek the
safety of a building or a hard-top vehicle any time they hear
thunder, even if it is not raining. They say lightning can strike as
far as sixteen kilometers from any rainfall. Lightning can travel
sideways. And at least ten percent of lightning happens without any
clouds overhead that you can see.
People who are outdoors should make sure they are not the tallest
thing around. Bend low to the ground, but do not lie down. And do
not stand near a tree or any tall object. Get away from water and
anything made of metal. A car is safe, but do not touch any metal
inside.
Safety experts say people in buildings should stay away from
anything with wires or pipes that lead to the outside. The National
Weather Service says if you plan to disconnect any electronic
equipment, do so before the storm arrives. Do not use a wired
telephone. Do not use water. All these can carry electricity.
Some people think a person struck by lighting carries an
electrical charge afterward. Experts say this is false. It is safe
to begin emergency treatment.
Each year about four-hundred people in the United States are
struck by lightning. Last year forty-four people died. The average
is close to seventy. The National Weather Service says that is more
than are killed by severe storms.
Lightning is a release of energy in the sky. So what causes it?
During a storm, the normally neutral particles in clouds hit each
other. They become electrically charged. As they flow toward each
other, they form an electric spark of light.
Some lightning is created within clouds. Some is created between
clouds. And some is created when negative charges move down from the
base of a cloud to meet positive charges rising from Earth.
Lightning strikes carry one or more electrical discharges called
strokes. The bright light seen in a flash of lightning is called a
return stroke. Return strokes travel at the speed of light. They
discharge about one hundred million volts of electricity. They heat
the air to more than thirty-three thousand degrees Celsius. Air
heated by return strokes expands and produces the sound of thunder.
This VOA Special English Health Report was written by Nancy
Steinbach. This is Phoebe Zimmbermann.