Lightning Knowledge

Lightning Q&A

Science

Is lightning common in summer?
Generally speaking, they tend to be concentrated in summer, around July to September. However, from November to March, the Sea of Japan side often experiences what is called winter thunder, which is rare in the world.
Is it true that there is lightning that moves from below to the sky?
Lightning does not always fall from the sky. If there is a very tall building or tree, it may discharge into the sky. This phenomenon is more common in winter lightning, and since the clouds are low, this phenomenon is not limited to tall buildings.
Is it safe if lightning strikes an airplane?
Airplanes are designed to be safe even if they are struck by lightning. The fuselage of an airplane is surrounded by metal, and the internal space of the airplane is not affected by external electricity. Therefore, even if lightning strikes an airplane, the lightning current will pass through the metal parts into the air, and the passengers on board will be safe.
Can you predict the approach of lightning?
There are devices that can detect the occurrence of lightning, so it is possible to predict lightning by using such devices. (This sound is not heard on FM radio.)
Is it possible to use lightning for something else?
Storing electricity from lightning has not yet been established with current technology. However, it does not mean that the electricity from lightning is not being used effectively at all. It is said that crops such as rice and mushrooms grow well in years when there is a lot of lightning, and in recent years there has been research into growing mushrooms by artificially generating electricity that simulates lightning.
Is there lightning in space?
Yes. In recent years, it has become known that lightning may occur on other planets besides Earth, such as Venus and Jupiter. Also on Earth, there is a phenomenon called sprites that emit light into space above thunderclouds. Sprites are instantaneous light-emitting phenomena that occur at altitudes between 40km and 90km, and are generated in conjunction with lightning near the ground. In addition to sprites, there are other luminous phenomena called blue jets and elves.

Safety Section

Is lightning more likely to strike people who wear jewelry made of precious metals?
The risk of lightning striking small metal objects such as glasses, watches, and necklaces is the same whether you are wearing them or not. Lightning tends to strike higher up, so if two people are walking side by side and one is holding an umbrella, lightning will basically strike the one holding the umbrella, even if it has a plastic or wooden handle that does not conduct electricity.
If I hear a rumble of thunder, is there a possibility of lightning striking?
If you hear the sound of thunder, there is a possibility of lightning. For example, if you hear a flash of lightning and then hear a rumble 10 seconds later, the distance to the point of lightning strike is 340m/s (speed of sound) x 10 (seconds) = 3400m. This does not mean that it is safe because it is still more than 3 km away. Under a thunder cloud with a diameter of 5km or 6km, lightning can strike anywhere.
Is it dangerous to swing a golf club when there is lightning?
Lightning has a tendency to strike high places, so swinging and holding long objects (especially metal objects) when lightning is rumbling is very dangerous. If you hear a rumble, do not hold anything taller than your height, such as golf clubs, fishing rods, or umbrellas.
Is it safe to go inside a car when there is thunder?
Cars, trains, and other vehicles with metal surfaces are safe to be inside when lightning strikes because the lightning will flow through the metal surface of the vehicle to the ground. However, do not touch the metal parts and stay in the center of the vehicle as much as possible.
Is it safe to hide my belly button when thunder is rumbling?
No. Although there is an old saying that the Lord of Thunder will aim for your navel, in reality, it is safest to go inside the building. It is safer to stay low during thunderstorms, so in a way it is also the right thing to do.
Will wearing a raincoat or rubber boots protect me from lightning?
No. Wearing rubber products will not protect you from lightning. The voltage of lightning is extremely high, and even rubber products, which normally do not conduct electricity well, will conduct electricity at the high voltage of lightning. (This is called dielectric breakdown.)
When lightning strikes, I run under a tall tree, but is it really safe?
No. If you go under a tall tree when lightning is rumbling, it is very dangerous because if lightning strikes the tree, it will fly from the tree to your body. This is called "side impact lightning". Stay 3 to 4 meters away from the tree and keep your posture low. The safest thing to do is to take shelter in a building or a car.
Is it safe to shelter from the rain in the eaves?
No. When it starts to rain, we tend to shelter from the rain in the nearby eaves, but lightning has the property of flowing over the surface of objects a lot, and if it strikes the roof of a house, it will flow from the roof to the exterior walls. If lightning strikes the roof of a house, it will flow from the roof to the exterior walls. It is dangerous to take shelter in the eaves, which are on the outside of the house, just as it is dangerous to run under a tree.

Home measures

Is a lightning rod sufficient for lightning protection?
Lightning rods are designed to protect buildings and people from lightning, so they cannot protect equipment inside a building. In order to protect equipment from lightning, a lightning arrester is necessary. What is the difference between a lightning rod and a lightning arrester?
Do lightning rods have to be installed in all buildings?
In Japan Lightning rods are required to be installed in buildings that are 20 meters or more above the ground and in buildings that handle hazardous materials such as chemical plants (Article 33, Building Standards Law). However, there is no obligation to install lightning rods in other general facilities.
Does lightning destroy electrical products?
Yes. Even if lightning does not strike directly, if lightning strikes nearby, it can enter the house through power lines and pipes buried underground. In this case, lightning can penetrate the outlets of televisions, telephones, computers, etc., and cause damage. This is called "induced lightning". In addition to power lines, lightning can also enter through telephone lines, antenna lines, etc.
Is it possible to protect various home appliances from lightning?
Yes, there is a product called a lightning arrester, and by installing the arrester in front of the power supply or the equipment you want to protect, it is possible to protect the equipment. When lightning from the power supply line or communication line enters the equipment, the lightning arrester works instantly to release the lightning to other places such as the ground. As a result, the electricity from the lightning will not flow to the equipment.
Where does lightning enter?
There are four main routes for lightning to enter.
  1. Power lines (power outlets, etc.)
  2. Communication lines (telephone lines, cable TV, internet lines, etc.)
  3. Antennas (TV antennas, etc.)
  4. Ground wires (such as ground wires)
These are the routes through which lightning can enter your home. By installing appropriate lightning arresters for each of these entry routes, you can protect your equipment.
What kind of equipment is most likely to be damaged?
Equipment that has more than one path for lightning to enter, such as fax machines, telephones, and the Internet, are most likely to be damaged. Also, devices that are located outdoors (for example, intercoms and solar power generators) are also likely to be damaged by lightning.
How exactly should I take countermeasures?
You can take simple measures yourself, such as using a power strip. All you need to do is to connect it to an outlet. You can also purchase a lightning arrester for a residential distribution board, but you will need to be certified as an electrician to install it.
What if my home appliances are damaged due to lightning?
In general, lightning damage to the building itself is covered by fire insurance. However, if your home appliances are damaged by lightning, you will not be covered unless you have fire insurance for your household goods. (Compensation differs depending on the insurance company and the contents of the policy, so please check with your insurance company for details.
I am considering solar power generation, but is there any lightning damage?
Since solar power generation equipment is located outdoors, it can be said to be susceptible to lightning, and according to a survey report by NEDO (New Energy and Industrial Technology Development Organization), the annual incidence of lightning damage is about 1-2%. Please consult with a lightning protection contractor about the installation of lightning arresters.

OTOWA websites use cookies to deliver and improve the website experience. See our cookie policy for further details on how we use cookies and how to change your cookie settings.