The research literature on the visibility of colors and topmarks used to code information used on buoys and other aids to navigation was reviewed. It is difficult to draw conclusions about the relative effectiveness of different topmark, color, and buoy configurations. Consequently, two experiments were conducted to determine the distance at which buoy topmark configurations could be correctly identified for different lighting geometries and background conditions. In experiment 1, the visibility of buoys and topmarks as separate entities was evaluated for ten different buoy configurations in simulated waterway viewing environments. Four buoys, including safe water, danger, port and starboard, were shown with and without topmarks, while two buoys, the north and east, always had topmarks. Front and back lighted buoys were presented in both water and foliage environments, as well as in a 'twilight' condition. In experiment 2 the visibility of buoys with integral topmarks was evaluated only for front lighting conditions. Analysis of the data from both experiments suggests strongly that topmarks did not increase the visibility the buoy configurations studied. The data indicated that color is a critical cue in determining buoy type, with significant differences in buoy detectability between red and green buoys. Front lighting also increased visibility distance significantly.

  • Supplemental Notes:
    • Sponsored by Coast Guard, Washington, DC.
  • Corporate Authors:

    Department of Energy

    Energy Efficiency and Renewable Energy, 1000 Independence Avenue, SW
    Washington, DC  United States  20585

    United States Coast Guard

    2100 Second Street, SW
    Washington, DC  United States  20593
  • Authors:
    • Collins, B L
    • Sanders, P A
  • Publication Date: 1992-3


  • English

Media Info

  • Pagination: 77 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00666677
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: NISTIR-4756
  • Files: TRIS
  • Created Date: Oct 3 1994 12:00AM