(1) The chief executive of a county council or a city council may, where he or she considers it is in the interests of road safety on a road, other than a national managed road, or part of such a road, in the administrative area of the county council or city council for which he or she is the chief executive, where road works are being carried out, by order apply to that road or part of it a special limit being a speed limit of not less than 20 kilometres per hour, as the speed limit on the road for mechanically propelled vehicles, in lieu of the speed limit provided or having effect under this Act in respect of the road or motorway or part of it.

(2) An order under subsection (1) is in force for the duration of the road works, subject to no such order having effect for a period of more than 12 months from the date of its making.

(3) The chief executive of a county council or a city council shall not make an order under subsection (1) in respect of a national road without the prior written consent of the National Roads Authority.

(4) Before making an order under subsection (1), the chief executive concerned shall notify the Commissioner in writing of his or her intention to make the order.