The Administrative Regulations on the Ship Radio Station Article 9

The priority of the operation for the ship radio communication are as following:1. Distress communication.2. Urgency communication.3. Safety communication.4. Communication for radio navigation and positioning.5. Communication for the navigational safety relating to the search and rescue operation by aircraft.6. Communication relating to the navigation and movement of ships, and weather observation messages destined for an official meteorological service.7. Other communications.
中文原文 船舶無線電臺管理辦法第9條
船舶無線電臺之通信,其優先順序如下:
一、遇險通信。
二、緊急通信。
三、安全通信。
四、有關無線電導航定位之通信。
五、有關與從事搜救作業航空器聯繫之航行安全通信。
六、有關船舶航行動態及發往氣象機構之氣象觀測報告通信。
七、其他通信。

English translation for reference only; the Chinese text prevails. Not legal advice.