(a) a cargo ship of less than 500 tons being a United Kingdom ship, the Secretary of State has reduced the said protective requirements; or

(b) a cargo ship of less than 500 tons not being a United Kingdom ship, the Government of the State whose flag the ship is entitled to fly has reduced the said protective requirements pursuant to paragraph 1.1 of regulation 54 of Chapter II-2 of the International Convention for the Safety of Life at Sea 1974;

the ship may comply with the reduced requirements instead of the full protective requirements.

    (3) This regulation shall not apply to ships or spaces intended for the carriage of dangerous goods in limited quantities as referred to in section 18 of the general introduction to the International Maritime Dangerous Goods Code.

    (4) Nothing in this regulation shall be taken to require duplication of anything already provided in a ship in compliance with other requirements of these Regulations.