Paragraph 11 Swimming and diving
A person must not swim or dive either on the surface or underwater without permission in the waters of the dockyard port within—
100 metres of the walls, slipways or boundaries of the Naval Base or any Crown Establishment;
150 metres of any of Her Majesty’s vessels or auxiliaries, or any foreign warship or auxiliary;
125 metres of either side of the recommended tracks for vessels navigating through Plymouth Sound to the Hamoaze for the time being shown on Admiralty charts;
the fairways of the dockyard port; or
an area in which anchorage is prohibited under paragraph 22.
A free-swimming diver must—
be individually marked with a short-scope orange marker buoy; and
the marker buoy must be lit with a white or amber light between sunset and sunrise.
A vessel engaged in diving operations must maintain a continuous radio watch on maritime VHF Channel 14.