INLAND ONLY Two power-driven vessels are meeting on a clear day and will pass less than half a mile apart. Which is TRUE in this situation for whistle signals?

Correct Answer: Option C — must be exchanged if passing agreements have not been made by radio

33 CFR 83.34(a) (Inland Rule 34) requires power-driven vessels in sight of one another to exchange whistle signals when passing within half a mile. However, this requirement is waived if a passing agreement has already been established via bridge-to-bridge radiotelephone, as the intent of the signal is satisfied.