Jack Lines

A jackline is a rope, wire or webbing strung from a ship's bow to stern to which a safety harness can be tethered, allowing a crewmember to move about the deck safely when there is risk of falling or being swept overboard. At sea, falling overboard is one of the leading causes of death in boating; fastening oneself to the ship with a safety harness tethered to a jackline reduces this risk.

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