A shipping master, surveyor, seamen's welfare officer, port health officer, Indian consular officer or any other officer at any port duly authorised in this behalf by the Central Government,-

(a) in the case of any ship upon which seamen have been shipped at that port, may at any time, and

(b) in the case of any Indian ship, may at any time, and if the master or three or more of the crew so request, shall, enter on board the ship and inspect-