Lightning Safety – What You Should Know
Highveld summers can mean only thing – soaring temperatures leading to welcome, but dangerous, late afternoon storms.
While lightning may be fascinating to watch, here are some lightning safety tips on why you should reconsider venturing out during a thunderstorm, and what to do if you’re caught out.
The Shocking Facts About Lightning Safety
According to the SA Weather Service, South Africa is ranked 3rd highest in the world for lightning-related deaths and injuries, with around 260 fatalities each year.
Electrical storms are most common on the Highveld, with storms in Johannesburg having a lightning “flash density” of 15 to 20 flashes per square kilometer per year, which is exceptionally high. Almost nowhere is completely free from the risks posed by lightning, with only a portion of the Cape peninsula considered by weather experts as being truly “lightning-free”.
- When a person is struck by lightning, they are exposed to an electrical shock which can cause life-threatening damage to internal organs, as well as severe burns, cardiac arrest and temporary paralysis. Getting immediate medical assistance, and performing CPR if necessary, is critical in these cases.
- If your house is struck by lightning an electrical charge can be imparted to metal pipes used for plumbing, sending a charge racing through the pipes which can connect to anything touching those pipes – including your showerhead and taps. Structural damage can include breaks and cracks in brick and concrete, damage to roof shingles and chimneys, and of course, fire.
- Household electrical systems can also be hit, when a bolt of lightning strikes a nearby power line and travels directly into a home’s electrical panel. If the surge is not stopped at the electrical panel by a form of “whole-house” surge protection, it can continue to travel through the wiring in the home, fusing wires together and damaging any electronics not plugged into a point-of-use surge protector. Determining the extent of this kind of damage can be difficult due to the location of the wiring within the walls of the property.
You simply can’t predict where lighting is going to strike, which is why lightning is a standard insured peril in most personal lines insurance policies.
Surge protection is a well-known method of protecting your home and gadgets against damage caused by lightning strikes, but it won’t help if you’re unexpectedly caught outdoors in a storm.
We’d like to share a few practical lightning safety tips you can follow to keep yourself as safe as possible from lightning strikes, but first it would be helpful to understand how lightning actually works.
The Physics of Lightning and Safety
National Geographic explains lightning as an electrical discharge caused by negative and positive charge imbalances between the storm clouds and the ground, or within clouds.
During a storm particles of rain collide inside clouds, increasing the voltage difference between the clouds and the ground and causing a negative charge in the lower portions of the clouds.
The earth, as well as objects on it such as trees and manmade structures, become positively charged, which creates an imbalance that is naturally corrected by the passing of current between the two charges. A typical lightning flash generates around 300 million Volts of current, compared to the household average of 120 to 240 Volts.
While cloud-to-ground and cloud-to-cloud lightning strikes do occur, it’s a little known fact that most lightning strikes actually travel from the ground to the clouds. This means that people and objects who are close to the area of discharge are at risk of acting as conductors for the charge on its upward journey.
Lightning Safety in the Storm
You can use this handy rule to estimate the distance that lies between you and an impending thunderstorm – if the time between seeing a flash of thunder and hearing the accompanying thunder is less than 15 seconds, the storm is only about 5km away. If the time gap is less than 15 seconds, the storm is closer and you should seek cover immediately and wait for it to pass.
- A building is the safest place to be during a thunderstorm, being sure to keep away from windows and not use any electronic equipment, including telephones and appliances. You should also avoid baths and showers during an electrical storm, especially if the property is not fitted with surge protection.
- If home is not an option, your next best place of shelter is a car, which acts as a Faraday cage by keeping any discharge on the outside of the vehicle. It’s recommended to pull over if you are driving and there is a danger of lightning strikes, as a blinding flash could cause an accident.
- If you’re stuck in exposed or elevated area like a golf course, it’s best to crouch near the ground with your feet together and your arms wrapped around your legs. Keep your head down, but don’t lie flat – keep your area of ground contact as small as possible. You should also be at least 3m away from other people, or objects that could act as conductors, including bicycles, trees, poles, masts, fence posts and metal fences.
- If you’re swimming or out on a boat, get to land as soon as possible. If in a boat, crouch down and avoid touching the rigging or anything metal.
Contrary to the popular expression, lightning can – and often does – strike the same place twice.
Keep these facts in mind this summer, and if a storm approaches take the necessary action to avoid potential injuries.
To check what your current home insurance policy says about lightning, or to request a quote, get in touch with our team today.