Lighting requirements in inland waters are different from those in international waters for ________.

• A. Additional signals are required for certain vessel types
• B. The colors used are different
• C. The timing of navigation lights is seasonal
• D. All of the above

Answer: (D)

On inland waters the lighting rules are tailored to the busy, close-quarters navigation and the types of vessels common there. That brings three kinds of differences from international waters:

First, there are additional signals required for certain vessel types. Inland traffic includes tows, pushers, dredges, ferries, and other specialized craft, and the rules add signals to clearly indicate their presence and operations in congested channels.

Second, the colors used for some signals can be different. To prevent confusion among the varied inland traffic, the color scheme for certain lights and signals is not identical to the international standard.

Third, the timing of when navigation lights must be shown can be seasonal. Inland practice may adjust lighting requirements to reflect changing daylight hours and local operating patterns.

So all of these factors—extra signals for specific vessel kinds, differences in signal colors, and seasonal timing—explain why lighting requirements on inland waters differ from those in international waters.