To which types of ships, and their companies, do The Ship and Port Facility (Security) Regulations 2004 apply?

The following types of UK ships, and non-UK ships in UK waters, when on international voyages and their companies: passenger ships (including high­speed craft which carry more than 12 passengers); cargo ships (including high­speed craft) of 500 GT and upwards: and mobile offshore drilling units. They also apply to Class A passenger ships (see UK passenger ship classes in Section D) operating domestic services within UK waters, and their companies.