Temporary or experimental speed limits
40.—(1) If the Department is satisfied that it is desirable to do so—
(a)in the interests of safety; or
(b)for the purpose of facilitating the movement of traffic,
the Department may, subject to paragraph (8), make an order under paragraph (2) or (3).
(2) The Department may by order prohibit the driving of motor vehicles at a speed greater than that specified in the order on—
(a)any particular road so specified;
(b)all roads in any area so specified;
(c)all roads;
(d)roads of any class so specified whether in a particular area or generally; or
(e)all roads other than roads of a class so specified.
(3) The Department may by order prohibit the driving of motor vehicles at a speed less than that specified in the order on any road so specified, subject to such exceptions as may be so specified.
(4) Without prejudice to section 17(5) of the [1954 c. 33 (N.I.).] Interpretation Act (Northern Ireland) 1954, any prohibition imposed by an order under paragraph (2) or (3) may be imposed—
(a)either generally or at times, on days or during periods specified in the order;
(b)on the speed of vehicles generally or of any class or description of vehicles specified in the order on any length or portion of the carriageway so specified.
(5) Subject to paragraphs (6) and (7), an order under paragraph (2) or (3) shall, unless previously revoked, cease to be in force on the expiration of 18 months from the date on which it came into operation.
(6) The Department may by order continue in force for a period specified in the order or indefinitely the provisions of any order under paragraph (2) or (3).
(7) Where the Department proposes to make an order under paragraph (6), it may by order under this paragraph continue in force the provisions of any order under paragraph (2) or (3) for a period not exceeding two years from the date on which those provisions first came into operation (whether as provisions of that or a previous order under paragraph (2) or (3)).
(8) Before making an order under paragraph (2) or (3) or (7), the Department shall give public notice of its intention to do so (including publication of a notice in at least one newspaper circulating in the area to which the order applies).
(9) An order under paragraph (2) or (3) shall not operate to increase any maximum or minimum speed limit imposed under any other enactment (including any other provision of this Order) with respect to roads, motor vehicles or the drivers of motor vehicles.