South Australian Consolidated Regulations

AUSTRALIAN ROAD RULES - REG 21

21—Speed-limit where a speed-limit sign applies

        (1)         The speed-limit applying to a driver for a length of road to which a speed-limit sign applies is the number of kilometres per hour indicated by the number on the sign.

Note—

"Length" of road is defined in the dictionary.

        (2)         However, if the number on the speed-limit sign is over 100 and the driver is driving a bus with a GVM over 5 tonnes, or another vehicle with a GVM over 12 tonnes, the speed-limit applying to the driver for the length of road is 100 kilometres per hour.

Note 1—

"Bus" and "GVM" are defined in the dictionary, and "vehicle" is defined in rule 15.

Note 2—

Five tonnes is specified for the definition of heavy omnibus in the Australian Design Rules issued under the Motor Vehicle Standards Act 1989 (Cth).

Note 3—

If the vehicle is an oversize or overmass vehicle, the vehicle may be restricted to a lower speed-limit under another law of this jurisdiction.

        (3)         A speed-limit sign on a road applies to the length of road beginning at the sign and ending at the nearest of the following:

            (a)         a speed-limit sign on the road with a different number on the sign;

            (b)         an end speed-limit sign or speed derestriction sign on the road;

            (c)         if the road ends at a T-intersection or dead end—the end of the road.

Note 1—

"T-intersection" is defined in the dictionary.

Note 2—

Rule 322 (1) and (2) deal with the meaning of a traffic sign on a road.

Speed-limit signs
Speed-limit sign (Standard sign)	Speed-limit sign (Variable illuminated message sign)
Other signs
End speed-limit sign	Speed derestriction sign

Note 1 for diagrams—

There is another permitted version of the speed-limit sign and the end speed-limit sign—see the diagrams in Schedule 3.

Note 2 for diagrams—

A speed-limit sign or end speed-limit sign may have a different number on the sign—see rule 316 (4).