“When thunder roars, go indoors.” So reads the safety manual released by the National Centre for Environmental Health in the US. This is because it is believed that, while rare, the chances of being struck by lightning increase when the human ear can hear thunder.
Not being outside for the duration of a thunderstorm is best practice. However, if you do find yourself outdoors, avoid open fields and hilltops, and don't shelter under tall, isolated trees. Lower-lying areas, such as a wadi or ravine, are safer than elevated surfaces.
According to National Geographic, while you should head to a low spot, lying down flat is not recommended, as lightning can move along the ground surface, and this current can be as dangerous as a direct lightning bolt.
Inside a car with a hardtop roof, with the windows wound up, is one of the safest places to be. The enclosed, all-metallic casing ensures that, were lightning to strike, the charge would go around outside the vehicle, suggests car retailer Arnold Clark, thus creating a Faraday effect and protecting those within.
However, it's best to avoid touching any metallic areas of the car, outside and in.
Likewise, avoid being near or coming into contact with fences, poles and other metal objects when outside, and even exercise caution in the home by avoiding electronic equipment.
According to the lightning safety tips, published by the Centres for Disease Control and Prevention, computers, laptops, gaming systems, washers and hobs – anything connected to an electrical outlet – is potentially risky to use during a thunderstorm.
This is because lightning can travel through electrical systems, metal wires and even through the plumbing if a house or building is equipped with metal rather than plastic pipes.
Cordless or mobile phones are safer to use than corded phones, and swimming and camping should be avoided during a thunder or lightning storm.
What happens when lightning strikes?
Most lightning strikes are not fatal. They can, however, cause temporary paralysis, unconsciousness and minor to major burns depending on the severity of the strike.
Some people report a temporary loss of hearing and sight.
More serious symptoms include seizures, cardiac arrest, electrical damage to capillaries and sensory loss.
How to help someone struck by lightning
No electric charge remains in a person struck by lightning, so help can be administered immediately, or right after alerting medical authorities.
A person who has been rendered unconscious by a lightning strike may appear not to be breathing or have a pulse, but the New York State Department of Health suggests reviving those who are unconscious first – using CPR – as they are at greater risk than those who can communicate.
Finally, according to the First-Aid Training Co-operative, victims may be confused or nauseous, so communicate with them accordingly and keep them calm until more help arrives.