COLREG Rule 21

Rule 21. Definitions

Rule 21. Definitions

(a) "Masthead light" means a white light placed over the fore-and-aft centreline of the vessel showing an unbroken light over an arc of the horizon of 225° and so fixed as to show the light from right ahead to 22.5° abaft the beam on either side of the vessel.

(b) "Sidelights" means a green light on the starboard side and a red light on the port side each showing an unbroken light over an arc of the horizon of 112.5° and so fixed as to show the light from right ahead to 22.5° abaft the beam on its respective side. In a vessel of less than 20 m in length the sidelights may be combined in one lantern carried on the fore-and-aft centreline of the vessel.

(c) "Sternlight" means a white light placed as nearly as practicable at the stern showing an unbroken light over an arc of the horizon of 135° and so fixed as to show the light 67.5° from right aft on each side of the vessel.

(d)" Towing light" means a yellow light having the same characteristics as the sternlight defined in paragraph (c) of this Rule.

(e)"All-round light" means a light showing an unbroken light over an arc of the horizon of 360°.

(f) "Flashing light" means a light flashing at regular intervals at a frequency of 120 flashes or more per minute.

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