How close do you have to be to a lightning strike in the sea for it to shock you? © Getty Images

How close do you have to be to a lightning strike in the sea for it to shock you?

In a thunderstorm, being totally immersed in sea water is often a better bet that hiding out on your boat or surfboard, even with the chance of sharks!

Asked by: Maggie Stills, Colchester

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Basic principles suggest that the answer is ‘very close’ – within maybe tens of metres – so long as you are totally immersed in the water when the lightning strikes. The electric current has to pass through your body to do you any harm, and the conducting sea water will carry a good deal of the current around your body. You are at much greater risk if you are protruding above the water in a boat or on a windsurf board, as I once was during a lightning storm in Australia. My answer was to get into the water and stay there – sharks notwithstanding.


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