Section 21 in Prevention Of Collision On National Waterways Regulations, 2002
21. Definitions.-
(a)"Masthead light" means a white light placed over the fore and aft centerline of the vessel showing an unbroken light over an arc of the horizon of 22.5 degrees and so fixed as to show the light from right ahead to 22.5 degrees abaft the beam on either side of the vessel. This light shall be placed as far as practicable at height above the hull of not less than 3 metres for vessels of 20 metres or more in length and 2 metres for vessels of less than 20 metres in length.(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 metres in length the sidelights may be combined in one lantern carried on the fore and aft centerline of the vessel. Sidelights shall be placed not less than 1 metre below the mast headlight.(c)"Stern light" means a white light placed as nearly as practicable at the stem 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 light aft on each side of the vessel.(d)"Towing light" means a yellow light having the same character as the "stem light" defined in paragraph (c) of this regulation.(e)"All-round light" means a light showing an unbroken light over an arc of the horizon of 360 degrees.(f)"Flashing light" means a light flashing at regular intervals.
