Question 16 ONC02 - Second Mate/Third Mate Unlimited Tonnage

The Correct Answer is C. **Why Option C is Correct:** The steering and sailing rules for vessels in restricted visibility (Rule 19 of the COLREGs – International Regulations for Preventing Collisions at Sea) apply universally to **all** vessels when they are "navigating in or near an area of restricted visibility." This is a fundamental safety requirement. The rules impose specific duties (such as proceeding at a safe speed, having engines ready for immediate maneuver, and listening carefully to fog signals) regardless of whether the vessel is international or inland, large or small, or equipped with specific technology. The danger arises simply from the presence of restricted visibility. **Why the Other Options are Incorrect:** * **A) only if they have operational radar:** This is incorrect. While having operational radar (and using it correctly, as per Rule 7 and Rule 19) imposes specific responsibilities, the fundamental requirement to follow the rules for restricted visibility applies to *all* vessels, including those without radar. * **B) in sight of one another in fog:** This is incorrect. If vessels are "in sight of one other," they fall under the rules governing vessels in sight (Rules 11-18) rather than the special rules for restricted visibility (Rule 19), even if the visibility *is* poor (e.g., light fog). Restricted visibility rules apply when vessels cannot see each other clearly due to environmental conditions. * **D) only if they are showing special purpose lights:** This is incorrect. Special purpose lights (such as lights for towing, fishing, dredging, etc.) indicate a vessel's status or operation, but they do not determine when the restricted visibility rules apply. Those rules apply based on the environmental conditions (the presence of fog, mist, heavy rain, etc.).