“authorised” means specially authorised by the Secretary of State;

“motor vehicle” has the same meaning as in the M1Road Traffic regulation Act 1984;

“road hump” means an artificial hump which is in, or on the surface of, a road and which is designed to control the speed of vehicles; and references to a road hump include references to any other works (including signs or lighting) required in connection with such a hump; F3. . .

“statutory”, in relation to a speed limit, means having effect by virtue of an enactment F4other than section 84(1)(b) or (c) of the Road Traffic Regulation Act 1984 (temporary and variable speed limits)F5; and

“traffic calming works”, in relation to a road, means works affecting the movement of vehicular and other traffic for the purpose of promoting safety or preserving or improving the environment through which the road runs.