ISO 12401:2004 specifies the requirements for performance, sizing, marking and test methods for deck safety harnesses and safety lines. It is applicable to harnesses and lines which are intended to be worn by all persons when in the exposed cockpit or on the working deck of a recreational vessel afloat. It is not applicable to dinghy trapeze harnesses, windsurfing harnesses, seat harnesses for fast motor boats and harnesses intended to protect against fall from a height.