How often should a sound signal be sounded for a vessel constrained by draft during restricted visibility?

A vessel constrained by draft is required to signal its presence in restricted visibility to ensure that other vessels are aware of its potential difficulties in navigation. According to the COLREGs, the correct protocol for sound signals in these conditions is to sound the appropriate signal at intervals of not more than two minutes. This regular signaling helps maintain safety by keeping other vessels informed about the location and movement of the constrained vessel, allowing them to take necessary precautions to avoid collisions.

The two-minute interval is balanced; it's frequent enough to communicate the vessel's position without being overly disruptive. This protocol is part of a broader set of navigational rules that emphasize safety and the prevention of accidents in visually limited situations. This method of signaling plays a crucial role in maritime communication, particularly when visibility is compromised.