How to prevent and avoid the occurrence of lightning tragedy is also put in front of the public again. In the face of the problem of “how to avoid lightning damage in summer”, then how can we not let this thunder fall down? The following 100 hundred safety net popularized the scientific methods of indoor and outdoor lightning protection in thunderstorm weather.
Three fatal injuries caused by lightning
“Lightning stroke is a strong discharge phenomenon produced by thunderstorm cloud, with current of tens of thousands of amperes and a large amount of heat energy, with instantaneous temperature of more than 10000 ℃. Its energy can destroy tall buildings and split trees. Injury to people and animals. ” Experts say that in recent years, the majority of people injured by lightning in the emergency department of the hospital are still open-air operators. Once struck by lightning, he said, there are three kinds of fatal injuries to human body:
One is to hurt nerves and heart. When the strong lightning pulse current passes through the heart, the victim will have vasospasm, cardiac arrest, and the heart will stop beating in serious cases; when the lightning current damages the brain nerve center, it will also make the victim stop breathing.
Second, burn. When the current and voltage act on the surrounding air, the local high temperature appears, and the instantaneous temperature can reach more than 2300 ℃. When the strong current passes through the body, it will cause electric burns, muscle lightning paralysis and even burning.
The third is internal injury caused by lightning shock wave. After this part of patients were struck by lightning, it may seem that there is nothing wrong on the surface, in fact, there has been skull fracture and visceral injury. “Some people come to the hospital looking good, but they die in two or three days.”. Chen Dongsheng said.
Saved by thunder
There’s nothing wrong with asking 120, but if you don’t do anything while you’re waiting, it’s a big mistake. “Lightning injury often occurs. People who are hit by lightning usually have cardiac arrest and respiratory arrest. This may be a phenomenon of” fake death “caused by lightning strike, and immediate on-site rescue is needed.” Chen Dongsheng told reporters that a few years ago, a middle-aged woman who was struck by lightning was transferred to the emergency department of southern hospital from another hospital when her heart stopped for six minutes, but she survived 100 minutes after doctors insisted on first aid. “The key to her survival lies in that she insisted on CPR and pressing first aid from the first time her family found out until she was sent to the hospital. The cardiopulmonary compression time of lightning stroke patients must be longer than that of other patients. Even if you haven’t saved your life in half an hour, you still have to keep doing it. “
It should be reminded that when rescuing the wounded due to lightning stroke, the near dead should be treated first. The rescuers should first pay attention to safety. There are lightning factors in the place of the accident. After the accident is transferred to a safe environment, they should first do external chest compression and artificial respiration, while doing 120 calls to the hospital, and adhere to the arrival of rescue personnel. Some people mistakenly think that there is still electricity in the human body, but they dare not touch him, resulting in the delay of rescue time.
In addition, keep the injured warm. If there are manic restlessness, convulsions and other mental symptoms, it is necessary to make a cold compress for the head. For the part of electric burn, only keep dry or bandage under emergency condition. Lightning may also cause the injured person’s clothes to catch fire. If the injured person’s clothes catch fire, immediately let him lie down so that the fire will not burn on his face. You can also sprinkle water on the wounded, or wrap the wounded in a thick coat or blanket to put out the fire. Cool the wound with cold water, then bandage it with clean cloth and send it to the hospital for treatment.
“The damage of lightning shock wave to human body is delayed. After being hit by lightning, even if I feel OK, I’d better go to the hospital to check whether there is visceral or skeletal damage. ” Expert advice.
Home lightning protection
Install lightning arrester, keep away from the external wall, and unplug all plugs
How to ensure the safety of household appliances and personnel?
First of all, the buildings shall be equipped with direct lightning protection facilities, such as lightning rod, down lead and grounding body, in accordance with the lightning protection design specifications.
Secondly, the power line, telephone line and TV signal line introduced into the house should be shielded and grounded, so that part of the lightning current will drain into the ground. In order to ensure safety, lightning arresters for household appliances can also be installed on the corresponding lines. For ordinary families, three arresters are needed: the first is single-phase power supply arrester, the second is television feeder arrester, and the third is telephone arrester. The function of lightning arrester is to shunt and limit the voltage of lightning electromagnetic pulse from the line, so as to realize the safety of household appliances protected by lightning arrester. “The arrester must be of good quality and be installed by professionals!” Chen said.
The installation position of household appliances should be as far away from the outer wall or column as possible. Also pay attention to regularly check the common ground wire used by household appliances. If the ground wire is loose or disconnected, the housing of household appliances may be electrified and the arrester may not work properly.
Of course, the most important thing is to rely on the lightning protection facilities of the building itself. If conditions do not allow, unplugging all plugs is an emergency measure.
In addition, in thunderstorm days, it is necessary to keep away from the rooftop and the outer wall of the building; avoid long metal objects such as railings and water pipes, and prohibit the solar water heater shower; the electrical and electronic equipment shall be closed as much as possible, and the fixed telephone shall be used less. There is no clear scientific basis for the saying of “calling a mobile phone to trigger thunder”. Experts believe that you can fight when you are far away from thunderstorms, and you’d better avoid it when you are near thunderstorms.
Step into the room outside the tall building, and go down the mountain quickly on the high mountain,
Swim in the water, go ashore
1. The first thing to do is to judge whether the thunderstorm is close to you. Once the lightning is on, start counting once a second (sound propagation speed is 340m / s). If there is 10 seconds when the thunder rings, it means that the thundercloud is still a certain distance away from itself. Try to find buildings with lightning protection facilities to avoid danger. But Lei Yun can walk very fast. If he is close to him, he should squat down in a low-lying place, with his legs together, and wait for the thunderstorm to pass. Drivers are safest in their cars.
2. Do not go under isolated trees or near tall buildings without lightning arresters to remove metal objects.
3. It is not suitable to take an umbrella or carry badminton or golf clubs on your shoulders in an open field.
4. Step into the room outside the high building, go down the mountain quickly on the high mountain, and swim in the water and go ashore quickly.
5. It is not suitable to drive motorcycles or bicycles.
6. Don’t hold hands. In case someone calls thunder, the one who holds hands will win at the same time.
As long as we do well in lightning protection measures, lightning damage to us is still very far away. Some of the above home appliances and outdoor sports lightning protection skills, I hope to be useful to you. If you have any questions about children’s home-based knowledge such as electric shock prevention, please continue to pay attention to Baibai safety net children’s electric shock prevention common sense column.