Which alarm is NOT part of the OOD comms equipment?

The correct choice is based on the understanding that the OOD (Officer of the Deck) communications equipment typically encompasses alarms designed to address immediate threats or situations aboard a naval vessel.

The Surveillance Alarm is primarily related to security and intelligence-gathering functions and is not classified under the essential alarms directly utilized for operational command and communication during crucial situations like navigation, collision avoidance, chemical threats, or general emergencies.

In contrast, the Collision Alarm is critical for alerting personnel of potential colliding vessels, the Chemical Alarm indicates the presence of hazardous materials, and the General Alarm functions as a comprehensive alert system for all personnel regarding any emergencies that require immediate attention. These latter alarms are integral to the safety and operational effectiveness of a naval unit, making the Surveillance Alarm the outlier in this context.