What type of watch must a compulsory Sea Area A1 vessel maintain?

A compulsory Sea Area A1 vessel must maintain a continuous Digital Selective Calling (DSC) watch on Channel 70. This is because Sea Area A1 is defined as the area within VHF coverage of at least one VHF coast station, which primarily relies on VHF communication. Channel 70 is specifically designated for DSC distress, urgency, and safety calls, making it essential for vessels operating in this area to monitor it continuously for safety and regulatory compliance.

A continuous DSC watch on Channel 70 ensures that the vessel can promptly receive distress alerts and safety communications, which are critical in an emergency situation. It is a requirement under the Global Maritime Distress and Safety System (GMDSS), which emphasizes the importance of maintaining proper communication protocols in different sea areas to enhance safety at sea.

Other channels, such as 8414.5 kHz and 2187.5 kHz, while used for specific purposes, are not the primary channels for vessel-to-vessel or vessel-to-shore emergency communications in Sea Area A1. Channel 16, although it's highly recognized for distress calling, is primarily for voice communications in VHF, whereas Channel 70 is dedicated to the DSC function. Therefore, maintaining a continuous watch on Channel