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Several people are killed by lightning every year in Japan. The number is very small compared with traffic accidents, but this is a tragedy that we wish to avoid at all costs. Here, we give some concrete examples of knowledge that can be used in daily life to protect yourself from lightning.
 
 

Sheltering from rain under the eaves of houses, and even close to walls and pillars indoors can be dangerous

 

In general, it seems quite easy to shelter from the rain under the eaves of a house. And many people believe that they will be safe inside a building. However, when lightning (electrical current) flows through an object, most of the current flows along the surface, with only a little through the center, in what is known as a skin effect. This means that eaves and the sides of pillars can be dangerous.

 
 
Sheltering from rain under the eaves of houses, and even close to walls and pillars indoors can be dangerous   Sheltering from rain under the eaves of houses, and even close to walls and pillars indoors can be dangerous
 
 
 

It is dangerous to shelter beside taller trees

 
It is dangerous to shelter beside taller trees  

The lightning’s (electric current) skin effect means that the sides of the trunks of trees are dangerous.

Skin effect: When a high frequency current flows through a conductor, the higher the current, the more the current tends to concentrate on the surface of the conductor.
 
 
 

Cars and trains are safe because they are earthed.

 
That’s right, cars and trains are safe. However, when driving a car, it is possible to become disoriented by lightning flash and thunder, so you should always stop and wait until the lightning has passed.
 
 
Cars and trains are safe because they are earthed.   Cars and trains are safe because they are earthed.
 
 
 

Know the correct information to protect yourself from lightning

 
  1. Tall, pointed objects are prone to lightning strikes. Correct
    If two people are standing side by side when lightning strikes, the one carrying an umbrella will be struck, even if the umbrella has an insulated, plastic handle.

     

  2. You are more likely to be struck by lightning if you are carrying metallic objects. Wrong
    It has been observed empirically that, as long as the metallic object is not protruding higher than your body, it has no effect on lightning strikes.

     

  3. Rubber boots, raincoats and other types of insulation will protect you from lightning. Wrong
    This has been proven to have absolutely no effect on lightning.

     

  4. If there is lightning nearby, it is dangerous to lie down on the ground. Correct
    Lying down on the ground will make it more difficult for lightning to strike you, but depending on where the lightning falls, current could run from your hands through to your feet, so this could be a dangerous thing to do.

  5. A direct lightning strike is fatal. Wrong
    Statistically speaking, even in the case of direct lightning strikes, about 20% of people survive.

     

  6. There is a safe zone of 45 degrees around the tip of a tall object. Correct
    Generally, this is held to be safe. However, this cannot be said when the height of the object goes over 30 meters.

     

  7. When a tall building or similar is struck by lightning, it is always from the tip. Wrong
    Lightning is more likely to hit the tip of a tall structure, but it can also strike the sides.

     

  8. Tall trees are safe to shelter under. Wrong
    It is actually dangerous to go too close to tall trees, and you should try to stay at least 2 meters from the tree’s trunk, branches and leaves. 

 
 

 

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