South Africa has one of the highest lightning ground strike densities in the world, and every year in summer rainfall areas lives are lost to this underrated natural hazard.

The best place to be in a thunderstorm is in a solid, properly-earthed building. Unearthed structures like tents and sheds offer no protection.

The second-best option is a stationary vehicle with metal sides and roof (the metal shell formed by the car helps deflect the electrical charge). Close the windows; lean away from the door; don't touch the steering wheel, ignition, gear lever or radio. Stay in the vehicle at least 30 minutes after the last thunder-clap.

If you're caught outside in a thunderstorm far from suitably protective buildings or vehicles, avoid the following:

• High, exposed areas
• Tall, isolated structures like trees and telephone poles
• Metal structures like fences
• Water.

If the lightning's right overhead, assume the "lightning position / crouch": squat with feet together, head tucked in, ears covered. Don't huddle in a group – spread out.

- Olivia Rose-Innes, EnviroHealth Editor, Health24, November 2011

More thunderstorm tips and info

More EnviroHealth Tips