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Lightning at Sea
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- Don't be a target!
Over 10% of deaths on cruising sailing boats alone at sea are caused by lightning. This is a tragedy to those families affected but one that we can take precautions to protect ourselves against...
Standing out as they do above the vast expanse of ocean water, marine vessels can be a prime target for a lightning leader seeking the most attractive path to ground - especially those with masts! Moreover, if the vessel does not have a metal hull and is not earthed to the water, the danger is multiplied considerably.
Often the most at risk are small boats, as these are more frequently constructed of wood or fibreglass, which are poor conductors of electricity, rather than metal - compared to the human body, which is an excellent conductor! Sailing vessels with portable masts, or vessels with the mast mounted on the cabin roof are particularly vulnerable as they are usually the least protected as far as grounding or bonding is concerned.
As incidence of lightning varies throughout the world, so logic dictates will the risk. However, while you may live in a region where lightning is relatively scarce, your sailing career may take you into areas of much higher risk. It is not unusual for the novice inshore sailor to become far more ambitious once the sailing bug takes hold
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to read more click here: http://www.moonraker.com.au/techni/lightning-marine.htm