[Code of Federal Regulations]

[Title 33, Volume 1]

[Revised as of July 1, 2005]

From the U.S. Government Printing Office via GPO Access

[CITE: 33CFR84.17]



[Page 216]

 

                TITLE 33--NAVIGATION AND NAVIGABLE WATERS

 

         CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY

 

PART 84_ANNEX I: POSITIONING AND TECHNICAL DETAILS OF LIGHTS AND SHAPES

--Table of Contents

 

Sec. 84.17  Horizontal sectors.



    (a)(1) In the forward direction, sidelights as fitted on the vessel 

shall show the minimum required intensities. The intensities shall 

decrease to reach practical cut-off between 1 and 3 degrees outside the 

prescribed sectors.

    (2) For sternlights and masthead lights and at 22.5 degrees abaft 

the beam for sidelights, the minimum required intensities shall be 

maintained over the arc of the horizon up to 5 degrees within the limits 

of the sectors prescribed in Rule 21. From 5 degrees within the 

prescribed sectors the intensity may decrease by 50 percent up to the 

prescribed limits; it shall decrease steadily to reach practical cut-off 

at not more than 5 degrees outside the prescribed sectors.

    (b) All-round lights shall be so located as not to be obscured by 

masts, topmasts or structures within angular sectors of more than 6 

degrees, except anchor lights prescribed in Rule 30, which need not be 

placed at an impracticable height above the hull, and the all-round 

white light described in Rule 23(d), which may not be obscured at all.

    (c) If it is impracticable to comply with paragraph (b) of this 

section by exhibiting only one all-round light, two all-round lights 

shall be used suitably positioned or screened to appear, as far as 

practicable, as one light at a minimum distance of one nautical mile.



    Note to paragraph (c): Tow unscreened all-round lights that are 1.28 

meters apart or less will appear as one light to the naked eye at a 

distance of one nautical mile.



[CGD 81-008, 46 FR 62447, Dec. 24, 1981, as amended by CGD 94-011, 63 FR 

5731, Feb. 4, 1998]