In this Act—

• " premises" includes any place and, in particular, includes—

  1. a

     any vehicle, vessel, aircraft or hovercraft;

  2. b

     any offshore installation ; and

  3. c

     any tent or movable structure ; and

• " offshore installation " has the meaning given to it by section 1 of the [1971 c. 61.] Mineral Workings (Offshore Installations) Act 1971.