Canadian maritime law requires 15 meters minimum for a buoyant device heaving line.

The U.S. Coast Guard does not specify a need for a heaving line.

The UK Broads Authority does not specify a length for heaving lines.

U.S. Coast Guard approved heaving lines come in lengths of 70 ft. and 100 ft. with an attached soft ball weight.

Heaving can be used as an adjective, for example, to describe a heaving stomach. Or it can be the present participle of the verb to heave.

The deck was heaving beneath her feet. Heaving mightily, he lifted the huge weight.

Dry heaving is hard gagging but not vomiting

He sat there heaving and panting because of the effort.

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