COLREG Rule 21 & Annex 1 Light And Shapes

Rule 21 Definitions of lights and shapes (a) “Masthead light“ means a white light placed over the fore and aft oenter line of the vessel showing an unbroken light over an arc oi the horizon of 225 degrees and so fixed as to show the light from right ahead to 22.5 degrees abai‘t 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 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on its respective side. In a vessel of less than 20 meters in length the sidelights may be combined in one lantern carried on the fore and at oentefline of the vessel. (c) ‘Stern light“ means a white light placed as nearly as practicable at the stern showing an unbroken light over an arc of the horizon of 135 degrees and so fixed as to show the light 67.5 degrees from right al’t on each side of the vessel.