Friday, May 13, 2016

Lightning and Thunderstorm : Concept, remedial measures and Bangladesh perspective.(বজ্রাপাত ও করণীয়)

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Md. Miznaur Rahman Mizan
Social & Institutional Expert
National Land Zoning Project, Ministry of Land.
Email: info.mmizan@gmail.com
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Yesterday, Bangladesh has experienced an extreme Lightning followed by thunderstorms which caused about 35 lives are dead including children and women. A much-awaited downpour brought with it thundershowers in 14 districts including Dhaka. This is not for the first time in Bangladesh; every year country has been experiencing this hazard. As per fellow meteorologist Sujit kumar Deb Sharma on an average lightning kills up to 300 people in Bangladesh. These numbers may be more since all cases are not reported to the media. The number of casualties is increasing rapidly in every year. Unfortunately, the policy maker and government agencies are taking serious attention on it especially for the rural people. Most of the casualties are happening in the rural area. It becomes demand time for the government to take necessary steps to reduce the damage to lives and property. In this article, I am going to give some necessary measure which could help the people to keep safe during Lightning and thunderstorm, and decline the intensity of death.
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What is LIGHTNING?


Generally, it is an atmospheric discharge of electricity, which typically occurs during thunderstorms, and sometimes during volcanic eruptions or dust storms.
LIGHTNING is a SPARK; Lightning a Gigantic Electrical Spark Traveling between Cloud to Cloud or Cloud to Earth-Containing an average charge of 30 to 50 lakhs Volts and a current of 30 Kiloamperes with a speed of 220 km per hour. (Abidur Rahaman, Dept. of Applied Physics and Electronics University of Dhaka, Bangladesh, Lightning Protection practices in Bangladesh: An overview)
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What to do and don’t during Lightning & thunderstorm:

Lightning is a beautiful and inspiring phenomenon, but it can be deadly. Fortunately, most lightning-related deaths are preventable. Following measure and step could help us to keep safe and reduce the damage of lives and property.

Part 1: Taking Shelter and Staying Safe

1.1: Find Shelter Immediately.

If you find yourself caught in a lightning storm, the key to minimizing danger is to get inside a protective structure. While most people seek shelter if lightning appears to be near, people commonly wait too long to seek shelter. If you can detect lightning, it may be close enough to strike you. Don’t wait for it to strike right next to you (or on top of you) to get to safety. Never stand under a tall or short tree, and avoid being close to power lines as they're both excellent conductors of electricity and could potentially cause death, if not the serious injury. Find a shelter near or under a stony shelter, stay a cavern or something.
  • Substantial, frequently inhabited buildings (those grounded with plumbing, electrical systems, and, if possible, lightning rods) are best. 
  • If you can’t find a substantial structure, get in a car with a metal roof and sides. If the car is struck, the metal body will conduct the electricity around you, not through you. Make sure all windows are rolled up and doors are closed. Be careful not to lean against any metal -- if you do, the lightning will be conducted into your body if it strikes the car. Do not use the radio. 
  • Avoid small structures, such as stand-alone public restrooms. Open covering and rain shelters are also not suitable. These structures will attract lightning and provide no protection, making them more dangerous to be around. 
  • Standing under a tree is a very bad choice. Lightning strikes tall objects, and if the tree you are standing under is struck, you may be struck as well or injured by the tree. 
  • Bring in your pets. Doghouses and other pet shelters are not suitable protection against lightning strikes. A pet leashed to a fence has a much higher risk of getting struck by lightning.

1.2: Stay away from windows.

Keep windows closed, and try to stay within inner rooms of the structure. Windows provide a direct path for the lightning to travel.


1.3 Don’t touch anything metal or electrical.

Using a landline phone is the main cause of lightning-related injuries in the US. Lightning can travel into the home from through any material that conducts electricity. This includes landlines, electrical wiring, and plumbing. 
  • Do not touch any electrical outlets during a storm. 
  • Do not unplug any devices during a lightning storm, as the strike could be transferred to you. 
  • Do not lie on concrete floors or lean against concrete walls. Most concrete has a wire mesh which can conduct electricity 
  • Stay out of the bathtub or shower, and avoid indoor swimming pools. 
  • In a car, try to avoid touching any part of the metal frame or the car's glass.


1.4. Stay inside.

Stay inside at least 30 minutes after the last strike. Don’t go out just because the rain is starting to let up. There is still a significant risk of lightning strikes from a departing storm.

Part 2: Surviving Thunderstorms Outside

2.1: Minimize your risk.


If you absolutely cannot reach shelter during a lightning storm, do everything you can to minimize your risk.
  • Move to a lower elevation. Lightning is much more likely to strike objects at higher elevations. 
  • Do what you can do get as low as possible? 
  • Avoid large open spaces where you are taller than anything else around you, like a golf course or soccer field. 
  • Stay away from isolated objects such as trees and light posts. 
  • Get away from unprotected vehicles, such as golf carts, and unprotected structures, such as picnic shelters. Avoid long metal structures, i.e. bleachers.

2.2: Get out of the water.

If you are fishing or swimming, get out of the water immediately, and move away from the body of water. Being near water is extremely dangerous during a lightning storm.


2.3: Spread out

  
  • If you are caught in a lightning storm with a group of people, maintain a distance of at least 50–100 feet (15.2–30.5 m) between each person. This will reduce the risk of lightning traveling from one person to another. 
  • Take a headcount after every close strike. This will ensure that anyone struck will get emergency attention quickly.


2.4: Remove Your Backpack

If you are hiking with a metal frame backpack, remove it as soon as you detect lightning. Make sure to leave it at least 100 feet (30.5 m) from wherever you are taking shelter. 


2.5: Assume the “lightning crouch”

  • Squat down with your feet together, your head tucked to your chest or between your knees, and your hands covering your ears or flat against your knees. 
  • Do not lie flat on the ground, as this gives the lightning a larger target. 
  • This is a difficult position to hold and it by no means guarantees your safety. However, by making it easier for a lightning strike to flow over your body rather than through vital organs, you may be able to sustain a smaller injury from it. 
  • Cover your ears and close your eyes to protect against nearby thunder and bright lightning flashes

2.6: Be alert for an imminent lightning strike.

  • If lightning is about to strike you or strike near you, your hair may stand on end, or you may feel a tingling in your skin.
  • Light metal objects may vibrate, and you may hear a crackling sound or "kee kee" sound. If you detect any of these signals, assume the lightning crouch immediately

2.7: Wear rubber boots.

They are made of a material which is a bad electrical conductor.


Part 3: Taking Precaution


3.1: Plan Ahead.


  • The best way to avoid injury from a lightning storm is to avoid it completely. Make your plans with dangerous weather in mind. Listen to the local weather forecast, and pay special attention to thunderstorm advisories.
  • Research the local climate: in some areas you can almost guarantee a thunderstorm on summer afternoons. Schedule your activities to avoid many high-risk situations. Those hot, muggy days are just the thing that a thunderstorm needs to get going



3.2: Watch the skies.


  • When you’re out and about, watch the sky for signs of approaching thunderstorms, such as rain, darkening skies, or towering cumulonimbus clouds.
  •  If you can anticipate lightning before the first strike, you can avoid being caught in a bad situation. Note that lightning can, however, strike even in the absence of these indicators.

3.3: Calculate the distance to the lightning

If conditions permit good visibility, and it’s not practical to seek shelter whenever you notice a strike, use the 30 second rule: if the time between a lightning flash and the resulting thunder is 30 seconds or less (aka 6 miles (9.7 km) or less), get to shelter immediately.

    3.4: Plan your response.

    If you are in an area that you expect will see lightning storms, know where safe shelters are. Communicate your plans to your group so that everyone knows what to do in an emergency.

    3.5:Prepare an emergency kit.

    Be ready with first aid and other disaster essentials. You may lose power during a thunderstorm, so have alternative light sources available.

    3.6: Install a lightning rod.


    • If you live in a lightning-prone area, installing a lightning rod can help protect your family and your property. 
    • Have your lightning rod professionally installed ? An incorrectly installed rod can increase the chance of a lightning strike

    Part 4: Treating Lightning Strike Victims

    4.1: Call Emergency Services.

    Because lightning strikes can cause cardiac arrest, aggressive resuscitation may be necessary. If you cannot dial to your emergency services, designate someone else to do it.

    4.2:Make sure it is safe to help.

    • Do not put yourself in danger trying to help a lightning strike victim. Either wait until the immediate danger has passed, or move the victim to a safer location. 
    • Despite the common myth, lightning can strike the same place twice.

    4.3: Start CPR (Cardio Pulmonary Resuscitation)



    4.4 :Treat the victim for shock.

    Lay the victim down on his or her back with the head resting slightly lower than the torso. Elevate and support the legs

    TIPS: AOB

    • Wear as much as rubber as possible. Rubber is a bad conductor and lightning will often bounce off it or sink into it. Also, avoid touching metal as lightning travels around metal and touching it will make it travel to you. 
    • Lightning can travel several feet through the ground, so distance yourself from tall, isolated objects. By the same reasoning, be aware that a person may have been hit by lightning, even if you didn’t see the lightning hit the person. 
    • Commercial lightning detection devices and weather warning services are available and should be considered for use by golf courses, parks, etc. 
    • Wearing portable electronics with headphones during a lightning storm can increase the likelihood of severe injury in the case of a strike - not only to the ears, but to anywhere on the body that the headphone cables lay against.


    Acknowledgment (Reference): 
    • Abidur Rahaman, Dept. of Applied Physics and Electronics University of Dhaka, Bangladesh, Lightning Protection practices in Bangladesh: An overview
    • Wikipedia, the free encyclopedia
    • wiki how and other internet sources
    • The New York Times

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