Lightning protection tips
Anticipate the coming of lightning
While listening carefully and watching the weather forecast, you can also estimate the coming of lightning through your own senses.
(1) Look up at the sky: When dense black clouds (cumulonimbus clouds) in the sky begin to accumulate, grow large and black, and develop quickly, lightning is likely to occur.
(2)Listen to noise: When you turn on the radio to listen to the radio, if you hear a harsh noise, it means that there may be discharge in the thunderstorm cloud nearby (however, be careful to distinguish it from possible electromagnetic interference nearby).
(3)Estimate distance: The easiest way to tell when lightning will reach the local area is to count the seconds as soon as you see the lightning. Because the speed of light is 300,000 kilometers per second compared to the speed of sound in the air 340 meters per second, there will be a certain time difference between the lightning and the accompanying thunder. If the time interval between seeing the lightning and hearing the thunder is 5 seconds, it means that the lightning flash occurs about 1.5 kilometers away from the position; If it is 1 second, that is, a blink of an eye, you will hear the thunder, indicating that the lightning flash location is about 300 meters nearby. When you encounter a thunderstorm, you can remember whether the time interval between hearing thunder and seeing lightning is getting longer or shorter each time, so as to judge whether the thunderstorm is gradually away or getting closer, so as to take certain preventive measures.
(4)Self-feeling: When you feel that your hair stands up or your skin has a strange feeling, it is likely to be struck by lightning, at this time, take immediate measures to protect yourself.
Outdoor lightning protection
Summer is a lightning season, if in the field activities, or in the journey encountered thunderstorms, if you take some measures in time, you can minimize the possibility of being hit by lightning.
(1)In the wild, especially in the journey, pay attention to listening to, watching or checking the weather forecast online, see the clouds, and judge whether there will be lightning weather.
(2)When thunderstorms occur, you should quickly take shelter in buildings protected by lightning protection devices, or deep caves. The inside of a car is an ideal place to avoid lightning strikes. If you are swimming or in a small boat, you should go ashore immediately, even if you are in a large boat, you should also hide in the cabin.
(3)When it is impossible to hide in a building with lightning protection facilities in the wilderness, stay away from tall and isolated objects such as trees, telephone poles, and chimneys. Do not stay near iron fences, metal clotheslines, overhead metal bodies and railway tracks. It is not appropriate to enter low-rise buildings such as field sheds and sentry posts without lightning protection devices. Keep away from transmission and distribution wires and overhead telephone cables. Try to avoid small areas that are particularly vulnerable to accumulation, such as rock fractures, large rock cracks, ground exits of buried pipes, and so on.
(4)Overhead lightning and thunder (commonly known as "thunder"), if you can not find a suitable lightning protection place, should find a low-lying place, as far as possible to reduce the center of gravity and reduce the body and the ground contact area, can squat, feet together, hands on the knee, bending forward, temporary avoidance, do not lie on the ground, if you can put on a raincoat, lightning protection effect is better. Be careful not to cluster together or hold hands together.
(5)Do not use umbrellas with metal tips in open areas, and do not carry farm tools such as shovels and golf clubs on your shoulders. It is best to remove the metal objects on the body when squatting for lightning protection, and place them a few meters away, especially the metal frame glasses worn.
(6)Do not swim or engage in other water sports and operations, such as working in rice fields, do not play outdoor sports such as ball games, climbing, riding, etc., leave the water and other open areas as soon as possible, and find a place with lightning protection devices for shelter.
(7)Do not drive a motorcycle, ride a bicycle, remember to run when thunder.
(8)In case of an unfortunate lightning strike, fellow travelers should call for help in time, and do artificial respiration and external heart massage for the wounded or fake dead.
Indoor lightning protection tips
When lightning comes, it is safer to hide indoors, but this is only relative to outdoor, if you do not pay attention to take measures indoors, in addition to the direct attack of spherical mines, more likely to suffer indirect lightning strikes.
Lightning protection measures:
(1)Be sure to close the doors and Windows
(2)Try to stay away from metal doors and Windows, metal curtain walls, and places with power sockets, and do not stand on balconies.
(3)Do not approach or touch any metal pipes indoors, including water pipes, heating pipes, gas pipes, etc.
(4)If there is no lightning protection device in the house, it is best not to use any household appliances indoors, including televisions, radios, computers, wired phones, washing machines, microwave ovens, etc., it is best to unplug all the power.
(5)Special reminder: Do not use solar water heater to take a bath in thunderstorm weather。
(6)If accidentally hit by lightning, take rescue measures in time.
Lightning protection measures for building
With the rapid development of modernization and the advent of the era of information technology, the emergence of high-rise buildings and the extensive use of electrical equipment and electronic equipment, the threat posed by lightning is becoming increasingly serious.
1.The use of comprehensive lightning protection technology, the lightning protection project as a system engineering for standardized design, serious construction, strict acceptance, frequent maintenance, regular inspection side, to ensure the safety and effectiveness of lightning protection devices.
2.Regular inspection side is a necessary measure for the late maintenance of lightning protection devices, at least before the arrival of the thunderstorm season every year, the legal inspection side technical organization should conduct a comprehensive inspection side of the lightning protection device, and evaluate the safety performance of the lightning protection device, so that the user can formulate the corresponding lightning disaster emergency plan.
3.The unit shall set up a person responsible for lightning disaster prevention, be responsible for lightning protection safety work, establish various lightning protection safety work, establish regular inspection rules for various lightning protection devices, check after thunderstorms and routine maintenance systems. If the lightning protection device is damaged after a thunderstorm, replace it in time.
4.In the design and construction of lightning protection devices, the construction unit should adopt a safe, reliable, technologically advanced, economical and reasonable design and construction scheme according to the factors such as geology, soil meteorology, environment, the characteristics of the protected object and the law of lightning activity.
5.Lightning protection products with technology and quality that meet national standards should be used to avoid the use of shoddy lightning protection products.
6.When changing, expanding buildings or adding new equipment, the original lightning protection device should be redesigned and constructed, such as: re-laying the computer network line, shifting and raising the outdoor antenna, etc., the original lightning protection device should be redesigned and constructed.
After a lightning disaster occurs, it is necessary to report the situation in time for investigation and handling to prevent lightning strikes from happening again.
Lightning damage to the human body
1、Direct lightning strike
A direct lightning strike is when the lightning strikes the victim directly, at least initially through the body of the entire lightning current, and most likely from the head, through the torso, through the soles of the feet into the ground. This is the worst case scenario for victims. Therefore, there are many successful cases of suspended animation rescue after being struck by direct lightning, and there are even reports of brief coma after being struck by direct lightning, and the breathing and heart beating have not stopped, so when lightning causes suspended animation (stop breathing, stop the heart beating, but no purple and blue plaques or spots on the body), you should not give up or stop rescue.
2、Contact lightning strike
A contact lightning strike is when lightning strikes another object so that the person touching the object becomes the victim. Exposure to lightning often causes temporary paralysis, sometimes coma or even death, but in general, it is less severe than direct lightning. Contact lightning strikes occur much more often than direct lightning strikes.
The side flashover and the above mentioned contact lightning strikes are common because the lightning does not directly hit the victim, but hits the object near the victim, because the lightning object has a high potential, and flash discharge to the person near it. Sometimes due to distant objects are struck by lightning, the high potential can be directly transmitted through the metal wire, or the high potential can be induced to cause side flashover resulting in casualties.
Step voltage is when lightning current flows into the ground, due to the existence of soil scatter resistance, the ground surface potential distribution, it is customary to call this flared potential distribution curve. There is a potential difference between the two points in this trumpet curve, which is obviously related to the current intensity, soil resistivity distribution, and stride length. Under the same soil condition, the greater the current intensity, the larger the step length, and the higher the stride voltage. When a person or animal stands on the ground with a trumpet potential distribution, the potential difference between the two feet is large enough to cause an electric shock or even death. If you encounter a thunderstorm in the field and can't avoid it, it is safer to squat down and tuck your feet together than to take a long stride.
Lightning burn and its first aid treatment
The thermal effect of electric current when lightning strikes the human body can cause electrical burns. However, electric burn is different from the general burn, there are electric shock, such as loss of consciousness, dizziness, nausea, palpitations, tinnitus, fatigue and other phenomena appear, the severe may occur breathing, cardiac arrest. There are also cataracts and nervous system damage that appear later after lightning strikes.
(1)If the clothes of the lightning strike catch fire, you can wave water on the body, or wrap the body in a thick coat or blanket to extinguish the flame. Those on fire should not run in panic, but roll on the ground to extinguish the flame, or lie in a depression or pool with water to extinguish the flame.
(2)Pay attention to the phenomenon of unconscious loss and respiratory and cardiac arrest in the lightning strike, first perform cardiopulmonary resuscitation, and then treat the electrical burn wound.
(3)For the treatment of electrical burns, cool the wound with cold water, then cover the dressing, for example, put a clean handkerchief over the wound, and then bandage it with a clean cloth. If there is no dressing, clean sheets, sheets, clothes, etc. can be wrapped and transferred to the hospital.
In principle, the injured should be transferred to the local hospital, if the local unconditional treatment needs to be transferred, should grasp the transport time, require the injured respiratory tract unobtrusive, no active bleeding, shock basically under control, infusion during transport, and take measures to combat shock, and pay attention to reduce the road turbulence.