What does the term "scan" refer to in watchstanding?

The term "scan" in watchstanding refers to actively looking for hazards or other vessels in the vicinity. This action is crucial for ensuring safety at sea, as it involves maintaining situational awareness to detect potential hazards that could impact the vessel's navigation or safety. A watchstander must regularly visually inspect the horizon and surrounding area, watching for other ships, obstacles, or any changes in the environment that could pose a threat. This vigilant scanning helps prevent collisions and ensures safe passage, making it one of the fundamental responsibilities while on watch.

Monitoring weather conditions, checking instruments, or communicating with other ships are important tasks as well, but they relate to different aspects of maritime operations. While they can complement the process of scanning by providing additional context or information, the primary definition of "scan" focuses on the visual assessment of the environment to maintain navigation safety.