In periods of reduced visibility or whenever a vessel operator needs to signal his or her intentions or position, a sound-producing device is essential. The navigation rules for meeting head-on, crossing, and overtaking situations are examples of when sound signals are required.
These requirements apply to vessels operating under engine power on New Hampshire waters.
- Vessels less than 16 feet long must have a hand, mouth, or power whistle.
- Vessels 16 feet to less than 26 feet long must have a hand, mouth, or power whistle audible for one-half mile.
- Vessels 26 feet to less than 40 feet long must have a bell and a hand or power whistle audible for one mile.
- Vessels 40 feet long or longer must have a bell and a power whistle audible for one mile.
These requirements apply to vessels operating on federally controlled waters.
- Vessels less than 39.4 feet (12 meters) in length, which includes PWC and “ski craft”, must have some way of making an efficient sound signal. Examples are a handheld air horn, an athletic whistle, an installed horn, etc. A human voice is not acceptable.
- Vessels that are 39.4 feet (12 meters) or more in length must have a sound-producing device that can produce an efficient sound signal. The sound signal should be audible for one-half mile and should last for 4 to 6 seconds.