Seafarer's Service Regulations Article 6

Cadets shall be at least 16 years old.The onboard internship period of deck, engineer, and electric cadets shall not surpass two years.During the onboard internship period, the cadets shall be considered seamen.
中文原文 船員服務規則第6條
實習生應年滿十六歲。
航海、輪機及電技實習生在船實習期間不得超過二年。
實習生在實習期間視同海員。

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