Md Jahedul Islam

When a large amount of charge accumulates inside the cloud than a large sparks occur inside the cloud. This is commonly known as electric shock. Sometimes the charge accumulates so much that they create an opposite charge towards the Earth and after ionize the air it travels millions of miles for reached to the ground in the surface. This is called lightning. At this time the air temperature increases to about 27000°c and the pressure increases to about 10-100 times during the formation of narrow ionized and electrically conductive channels.

This entire event takes place in a few thousandths of a second. This change causes the surrounding air to expand like an explosion at high speeds. This results in loud noises during lightning strikes. Lightning is a natural phenomenon formed by an electrostatic discharge through the atmosphere between two electrically charged regions. Lightning generates a huge amount of energy. A typical cloud-to-ground lightning strike produces about 1 billion joules of energy. The lightning flash produces a current of about 300 million volts and about 30,000 amperes. In normal houses where 220 volt electricity is used.

Lightning mainly depends on the geographical location of a country or region. There is no fixed period of lightning. However there is a 100% chance of rain during storms. Lightning has increased due to various reasons. Significant causes of lightning include climate change, weight loss. Also lightning has many causes like destroying of trees, mountains and environment etc. Due to the negative effects of climate change the lightning has been increasing recently. If lightning can be heard within 30 seconds of seeing the lightning strike then it means that it is close to us and we are likely to be harmed by it. Another if we hear the sound 30 seconds after the lightning strike then we must understand that it is far away from us and we are not likely to be harmed by it. At that time it is best to move to a safe place as quickly as possible.

In addition to the loss of life of people and animals there are many types of electrical equipment are damaged in lightning strikes. Due to lack of awareness the amount of damage caused by lightning is increasing day by day. Staying indoors or in a safe place during a lightning strike is less likely to kill us. However if the lightning strikes directly on the human body then the human body dies due to the excessive current flow in the human body. This occurs due to heart failure.

It is a common misconception and superstition of our society that the bodies of dead people are magnetized (turned into valuable magnets). On the other hand electrical appliances are constantly being damaged due to lightning strikes. It is not the case that electrical and electronics devices will be damaged by lightning. But in case of accidental lightning strike directly on the electrical service drop line all types of electrical and electronic devices used in the lightning strike will be destroyed. These equipments are constantly damaged during lightning strikes.

The amount of electrical and electronics devices destroyed during lightning strikes is unprecedented. During this time, people's refrigerators burn, TVs burn, and so on. A lightning strike over a power line renders our devices overcharged and useless. That's why we can protect the devices with devices like UPS or stabilizers. Care should be taken to ensure that the device is not plugged in during a lightning strike. For this reason it is better to turn off the router during lightning. Not only the router it is safe to unplug all other electrical appliances.

Similarly it is better not to charge the mobile phone during lightning. It is safe to unplug the laptop and run it on battery power. If possible the dish connection of the TV should also be disconnected. It is better to run the refrigerator with a voltage stabilizer. Smartphones can be used indoors during lightning strikes. But at this time it is better to keep the internet off. In case of severe lightning it is better to keep the smartphone completely off.

If not then the smartphone may be dangerous for the person who are using this. It is possible to keep them safe only by keeping the electrical connection of TV, fridge, mobile, laptop, WiFi open during lightning. A home or office cut-out is essential to protect any electronic device during a lightning strike. It is best to have the connection checked by an electrician regularly. Some urgent steps need to be taken to avoid damage to people and electrical equipment due to lightning.

Computers, routers, televisions, refrigerators and other electrical appliances should be switched off when there is a glimpse of lightning. Thunderstorms can occur even when we are outdoors. However if we see such a situation before going out it is possible to avoid the risk of damage due to lightning if you switch off various technology products including computers, routers. Televisions are more damaged due to lightning. The main reason for this is that the dish line is connected to the television. As a result if there is lightning in an area there is a possibility of easily damaging the TV through the dish line. Many people use TV cards in computers.

As a result it is normal for the computer to be damaged due to dish line connection during lightning. In this case it is better to keep the dish connection open during lightning. Through this process the technology products will be protected and safe. Routers and electronic devices related to networking are the most affected by lightning. The risk of router damage is usually highest during lightning strikes. Due to the increased use of technology and infection during the Corona period from taking online classes to studying as well as entertainment everything is done with broadband lines and WiFi internet connections. The use of WiFi has also increased day by day. WiFi is a type of wireless internet connection.

It works with the help of router. This router requires a power connection to connect to the Internet. It is not the case that router will be protected by simply shutting down the electricity lines of the router when there is a glimpse of lightning. If we can keep the LAN cable from the router to the Internet connection open then it will be more secure. However if optical fiber cable is used for internet connection the risk of lightning damage is less. Because optical fiber cables do not use metallic wires. People's dependence on technology is increasing day by day. Earlier various electrical appliances were seen in the homes of the upper class but now a days the upper middle class and middle class are also using many electrical appliances, such as AC, washing machine, oven, deep fridge.

A lightning can send a surge of electricity through connected wiring. It is not impossible to destroy electrical devices and circuits as a result. Some appliances, such as toasters, refrigerators, vacuum cleaners and music systems, contain circuit boards with ICs. Therefore to protect home and office components from lightning the earthing measures must be taken including using electricity control equipment in these devices. In a house or office electrical connection there are one is main line and the other is neutral line. This neutral line is buried in the ground with a rod or wire called earthing. It is used to conduct electricity safely to ground after a lightning strike. When excess voltage or current flows due to lightning then it is safely brought down to earth through earthing. As a result many valuable devices are saved from destruction. It is very important to use a good quality multiplug for electronics devices.

It is better to use multiplugs that regulate the flow of electricity in self-control automatic systems. As a result even during high voltage or lightning there will be no harmful effect on the device connected to the multiplug. Thunderstorms are forecasted on radio, television or websites based on radar or satellite data. However it is now possible to get clear information about the exact place and time of lightning through new detective sensors. It is possible to tell the level of lightning and lightning 10-15 minutes in advance with the information stored in the detective sensors. Apart from this, clear information regarding the area and duration of lightning is available through this detective sensor.

If lightning warning is immediately published on the website of the Meteorological Department in real time and if this information is communicated to the people of the concerned area through SMS on mobile phones, the loss of many lives can be reduced. Also if it is possible to reach this information to the people of the concerned area then it will be possible to keep the used electrical and electronics devices be safe.

The writer is a Network Technician (ICT Cell) Jagannath University, Dhaka