What if I were struck by lightning?
Initially this seems like a fairly straightforward question. As it turns out, there are several ways a person can bestruck by lightning, and the type of strike dictates the impact it can have on your body.
- Direct strike - a cloud-to-ground lightning strike hits you or something you're holding, like a golf club, dead-on instead of reaching the ground.
- Side flash - lightning strikes something close to where you are standing and then jumps from that to you.
- Contact potential - while you're touching something, like a fence-post or a tree, lighting strikes that object and the current travels from the object through the point of contact into your body.
- Step voltage - you're sitting with your feet together in front of you, knees up and rump settled on the ground near a spot where a cloud-to-ground lightning strike hits. As the lighting current disperses, it travels through your body by entering one point, say your joined feet, and exiting another, your rear end.
- Surge voltage - while you're using some type of electrical appliance or atelephone, lighting strikes the source of power or network connected to the device and you receive a shock.
The worst kind of lightning experience is a direct strike - statistically, it's the most fatal. Being hit by a side flash or through contact potential are the next in the level of severity, with step voltage third and surge voltage last. Basically, the amount of current and voltage going through your body lessens with each of these types of strikes. If you're a victim of a direct strike, the full impact of the lightning courses through your body. In the other scenarios, the intensity is lessened because some of the energy is dispersed elsewhere.
The circulatory, respiratory, and nervous systems are most commonly affected when a person is struck by lightning:
Circulatory: Reportedly, the majority of fatalities resulting from direct strikes are due to cardiac arrest. Ironically, were someone nearby with an automatic external defibrillator, to administer another electric shock to the heart, the victim might survive.
Respiratory: The greatest threat to the respiratory system is paralysis. Artificial respiration is required so the victim won't die from lack of oxygen.
Nervous: When the central nervous system is affected, a number of side effects can occur such as dementia, amnesia, temporary paralysis, impaired reflexes, memory gaps and anxiety or depression.
Lightning will strike anything that stands high above the ground. Trees are a favorite target. No one knows how lightning determines its jagged path. Brought to you by the Discovery Channel.
Extreme weather has been causing death and destruction around the world. Near the Xinjiang province of China, high winds brought disaster, blowing 10 carriages off the tracks, leaving three passengers dead and 34 injured. In Sydney, fierce rain storms caused flash flooding where one man was struck by lightning and 11 school children barely escaped injury when their classroom was hit.
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How do I avoid getting struck?
More than 1,000 people get struck by lightning every year in the U.S., and more than 100 of them die as a result of the strike. Lightning is not something to toy with. There are several precautions you can take to guarantee your safety in a storm.
If you're outside:
- Always look for appropriate shelter in a building or a car. Most people think it is the rubber tires that keep you safe in a car because they do not conduct electricity. Actually, in strong electric fields, rubber tires become more conductive than insulating. The reason you are safe in a car is because the lightning will travel around the surface of the vehicle and then go to ground. This occurs because the vehicle acts like a Faraday Cage. Michael Faraday, a British physicist, discovered that a metal cage would shield objects within the cage when a high potential discharge hit the cage. The metal, being a good conductor, would direct the current around the objects and discharge it safely to the ground. This process of shielding is widely used today to protect the electrostatic sensitive integrated circuits in the electronics world.
- Avoid taking shelter under trees. Trees attract lightning. Put your feet as close together as possible and crouch down with your head as low as possible without touching the ground - remember step voltage - you only want one contact point with the ground. Never lay down on the ground for the same reason; you never want the current to have the ability to pass through your body.
If you're inside:
- Stay off the phone. If you must call someone, use a cordless phone or cell phone. If lightning strikes the phone line, the strike will travel to every phone on the line and potentially to you if you are holding the phone.
- Stay away from plumbing pipes (bathtub, shower). Lightning has the ability to strike a house or near a house and impart an electrical charge to the metal pipes used for plumbing. This threat is not as great as it used to be, because PVC (polyvinyl chloride) is often used for indoor plumbing these days. If you are not sure what your pipes are made of, wait it out.
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