Lightning Safety

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Lightning Safety
Oklahoma Dept of Corrections Staff
Organizational Development
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Course Information

• Data source National Oceanic Atmospheric
  Administration (NOAA), U.S. Dept. of Commerce.
  Website http//www.noaa.gov
• Photography All photos, including title
  background, are courtesy of NOAA.
• Course design Lynne Presley, Oklahoma Dept. of
  Corrections, Staff and Organizational Development
  Unit,lynne.presley_at_doc.state.ok.us
• Course published October 12, 2005. Oracle
  SAFI39000.
• Course credit One hour (assuming all links are
  followed).

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Course Objectives

• At the end of this course, students will be able
  to
• Understand the different ways that cloud to
  ground lightning can kill people.
• Name at least 2 physical injuries that a
  lightning bolt can cause.
• Calculate a storm's distance by using the "Flash
  to Bang" method.
• Understand indoors and outdoors safety
  precautions to avoid being struck by lightning.

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Introduction

• Did you know that lightning is the second-leading
  weather killer in the U.S.? (Floods are number
  one.) Lightning is more deadly than tornadoes or
  hurricanes. According to the NOAA, lightning
  strikes in the U.S. kill over 70 people and
  injure hundreds more each year.
• According to the NOAA
• Approximately 25 million cloud to ground
  lightning strikes occur in the U.S. each year.
• The air within a lightning strike can reach
  50,000 degrees Fahrenheit.
• Lightning can heat its path five times hotter
  than the surface of the sun
• One ground lightning strike can generate between
  100 million and 1 billion volts of electricity.

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How Lightning is Formed
Lightning is caused by the attraction between
positive and negative charges in the atmosphere,
resulting in the buildup and discharge of
electrical energy. This rapid heating and
cooling of the air produces the shock wave that
results in thunder. During a storm, raindrops
can acquire extra electrons, which are negatively
charged. These surplus electrons seek out a
positive charge from the ground. As they flow
from the clouds, they knock other electrons free,
creating a conductive path. This path follows a
zigzag shape that jumps between randomly
distributed clumps of charged particles in the
air. When the two charges connect, current
surges through that jagged path, creating the
lightning bolt. (NOAA)
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How Lightning is Formed, cont'd.
Lightning flashes don't always strike the ground.
They can occur within a cloud, or from cloud to
cloud.
NOAA
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Lightning Damage
Cloud to ground lightning can injure and kill
people in different ways. For instance,
lightning can strike and hit a person directly.
Lightning can also branch off to a person from
another object, such as a tree, pole, or other
tall object. Also, lightning may travel through
power and phone lines and plumbing pipes to a
person who is in contact with an electric
appliance, telephone, or plumbing fixture.
Lightning striking the Eiffel Tower,June 3,
1902, at 920 P.M. NOAA
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Lightning Damage, cont'd.
These cows were killed when lightning struck the
fence, and the current traveled along the fence
killing the cows. Photo NOAA/Ruth Lyon-Bateman
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Physical Injuries

• Lightning strikes can produce a variety of
  physical injuries and disabilities, including
• Cardiac arrest
• Brain damage and nervous system injuries
• Pain and bodily damage from being thrown by the
  strike
• Impaired thinking and mental confusion
• Burns
• Death
• On average, 20 of lightning strike victims die,
  and 70 suffer serious long-term effects.

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Lightning Warning Signs

• High winds, rainfall, and a darkening cloud cover
  are the warning signs for possible
  cloud-to-ground lightning strikes.
• Things to remember
• If you can hear thunder, lightning is close
  enough to strike your location.
• Lightning can strike miles away from any
  rainfall. Lightning can also travel sideways for
  many miles. If you hear thunder, look for cover.

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Storm Proximity

• It's not uncommon to see a flash of lightning,
  then hear the thunder some seconds later. It's
  possible to estimate how close the storm is by
  using the "Flash to Bang" method. According to
  NOAA, it's very simple
• Once you see a lightning flash, start counting
  the seconds until you hear the thunder.
• Divide the number of seconds by 5 to get the
  distance in miles.
• Example
• If thunder is heard The lightning is
• 10 seconds after a flash 2 miles away

10 seconds divided by 5 2 miles
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Safety Precautions - Inside

• There is no way to guarantee that you won't be
  hit by lightning. However, taking safety
  precautions can reduce the risk.
• A house or substantial building offers the best
  protection from lightning. Why? Because they
  have pipes and wires going into the earth, which
  grounds the structures. Be sure to follow these
  safety tips from NOAA while in a house or
  building during the thunderstorm
• Avoid contact with corded telephones, electrical
  equipment, and cords.
• Avoid contact with plumbing. Do not wash your
  hands, do laundry, wash dishes, or take a shower
  or bath.
• Stay away from windows, doors, and porches.
• Do not lie on concrete floors, and do not lean
  against concrete walls (the concrete may contain
  wire mesh, which can conduct electricity).

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Safety Precautions Outdoors

• Remember that NO OUSIDE LOCATION IS SAFE DURING A
  THUNDERSTORM! However, if you are outdoors when
  a thunderstorm occurs, and you can't find shelter
  in a building, follow these NOAA safety
  guidelines to avoid the most hazardous locations
• Stay away from partially-open outdoor shelters,
  such as car ports, picnic shelters, tents, open
  garages, and covered patios.
• Some vehicles are safer than others. Safer
  vehicles include those with hard tops. Unsafe
  vehicles include convertibles, golf carts,
  motorcycles, bicycles, boats, and other vehicles
  with soft or no tops.

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Learn More About It
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Safety Precautions Outdoors

• There are other precautions you can take if you
  are outdoors when a thunderstorm occurs, and you
  can't find shelter in a building
• Do NOT seek shelter under tall isolated trees or
  poles. Lightning typically strikes the tallest
  object.
• Stay away from metal objects such as fences,
  wires and poles.

This isolated pole is a magnet for lightning!
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Warning Signs

• People sometimes receive a few seconds of warning
  before being struck by lightning. For instance,
  the following events have been reported
• Hair standing up
• Tingling skin
• Light metal objects start to vibrate
• Seeing a corona discharge (electrical spark)
• Hearing a crackling sound
• If you experience any of these warning signs, and
  cannot seek inside shelter, assume the position
  shown on the next slide.

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Safety Precautions Outdoors
If lightning is in the immediate area, and there
is no safe location nearby, get into the
"lightning crouch" position. Crouch down, but DO
NOT lay down. Bend your knees down while keeping
your feet together. (NOAA)
NOTE If you're with a group, everyone should
spread out so there are several body lengths
between each person. Once spread out, assume the
position shown in the picture to the right.
The "Lightning Crouch" position. NOAA
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First Aid
Being struck by lightning doesn't mean automatic
death. People who are struck by lightning don't
carry a charge it's safe to touch them and
provide medical treatment. Call 911
immediately, and conduct a basic first-aid
assessment, focusing on breathing and pulse.
Begin CPR as necessary while you wait for medical
assistance to arrive. (NOAA)
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Course Review
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Course Review Question 1of 10
1. The air within a lightning strike can reach
50,000 degrees Fahrenheit.
Click here for correct answer
Answer True
Click here for next question
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Course Review Question 2 of 10
2. Rapid heating and cooling of air during a
storm produces a shock wave that results in
_________.
Click here for correct answer
Answer Thunder
Click here for next question
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Course Review Question 3 of 10
3. Lightning flashes always strike the ground.
Click here for correct answer
Answer False. Lightning can also flash within
a cloud, and from cloud to cloud.
Click here for next question
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Course Review Question 4 of 10
4. Lightning can hit a tree, then travel to a
person.
Click here for correct answer
Answer True
Click here for next question
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Course Review Question 5 of 10
5. Being hit by lightning "jolts" the brain and
improves brain function.
Click here for correct answer
Answer False. Being hit by lightning can cause
brain damage, impaired thinking, and mental
confusion.
Click here for next question
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Course Review Question 6 of 10
6. High winds, __________, and a darkening cloud
cover are warning signs of a possible cloud to
ground lightning strike.
Click here for correct answer
Answer Rainfall
Click here for next question
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Course Review Question 7 of 10
7. The "Flash to Bang" method helps to identify
how close a storm is. Use the method to solve
this problem If thunder is heard 5 seconds
after a lightning flash is observed, how far away
is the storm?
Click here for correct answer
Answer 1 mile. To calculate the distance,
remember this formula of seconds divided by 5
distance in miles
Click here for next question
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Course Review Question 8 of 10
8. Taking an indoors shower or bath during a
thunderstorm does not increase a person's chance
of being struck by lightning.
Click here for correct answer
Answer False. Remember that electrical current
can travel through plumbing pipes and hit you.
Click here for next question
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Course Review Question 9 of 10
9. Why does a house or other substantial building
offer protection from being struck by lightning?
Click here for correct answer
Answer Because most houses and buildings have
pipes and wires going into the earth, which
"grounds" them and guides electrical currents
into the earth.
Click here for next question
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Course Review Question 10 of 10
10. It's a good idea to seek shelter during a
thunderstorm under the tallest tree you can find.
Click here for correct answer
Answer False. Lightning typically strikes the
tallest object in an area.
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Learn More About It
Want to learn more about lightning storms? Visit
these sites http//www.noaa.com/lightning.html T
he National Oceanic Atmospheric
Administration's "Lightning" web
site. http//www.nssl.noaa.gov/researchitems/ligh
tning.shtml The National Severe Storms
Laboratory's "Lightning" web site.
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Conclusion
Obviously, we want to avoid being struck by
lightning. We can improve our chances by
following the safety precautions in this
course. Stay alert, and stay safe!