21.—(1) On the arrival of an infected ship or a suspected ship, or any other ship on which there has been, during its current voyage and within the last four weeks before arrival, a case of a disease subject to the International Health Regulations in respect of which the ship has not, outside the United Kingdom, been subjected to appropriate measures equivalent to those provided for in these regulations, the master shall take it to a mooring station unless an authorised officer otherwise allows or directs.
(2) When the authorised officer has reason to believe that a ship on arrival may be one to which paragraph (1) of this regulation applies, he may direct the master to take it to a mooring station or to such other place as he considers desirable.
22. The authorised officer may for the purposes of these regulations direct that any ship from a foreign port shall on arrival be taken to a mooring station for medical inspection, and he may, if a customs officer is to be the first officer to board the ship, give a notice in writing of such direction to the customs officer, who shall deliver the notice to the master.
23. Where on the arrival of a ship from a foreign port it appears to a customs officer, from information in the Maritime Declaration of Health or otherwise, that the ship—
(a)has during its voyage been in an infected area; or
(b)is one to which regulation 21(1) applies,
he shall direct the master to take it to a mooring station for detention there unless an authorised officer otherwise allows or directs.
24. If after the arrival of a ship a case of disease subject to the International Health Regulations or of lassa fever, rabies, viral haemorrhagic fever or marburg disease occurs on board, or an animal infected with any such disease is discovered or suspected of being on board, the authorised officer may direct the master to take the ship to a mooring station.
25. A ship which has been taken to a mooring station or directed there by an authorised officer shall remain there until it has been inspected by the medical officer.
26. An authorised officer may detain, or give notice in writing to a customs officer to detain, any ship for medical inspection at its place of mooring (not being a mooring station) or at its place of discharge or loading.
27. The detention of a ship by a customs officer under these regulations shall cease as soon as the ship has been inspected by the medical officer or, if such inspection has not commenced within twelve hours after the ship has been so detained, on the expiration of that period:
28.—(1) The medical officer shall inspect any ship and the persons on board as soon as possible after it has been taken or directed to a mooring station or after it has been detained under these regulations.
(2) If the ship is one to which the authorised officer is required to apply any further measure under these regulations or additional measures in schedule 4, or if after such inspection he considers it necessary to apply any such further or additional measures he may detain the ship at the mooring station or at such other place as he considers desirable, or continue the detention, as the case may be, if such detention or continued detention is necessary for the application of such further or additional measures.
29. The authorised officer may require the master of a ship which under these regulations has been taken or directed to a mooring station or detained because rodents have been discovered or there are reasonable grounds for suspecting that rodents are on board to take all practicable measures to prevent the escape of rodents from the ship.