Abstract： AS 1742.4:2020 pdf download.Manual of uniform traffic control devices Part 4: Speed controls. The objective of speed management is to contribute to road safety, mobility and amenity on public roads by providing a system of speed limits that...

AS 1742.4:2020 pdf download.Manual of uniform traffic control devices Part 4: Speed controls.

The objective of speed management is to contribute to road safety, mobility and amenity on public roads by providing a system of

speed limits that are compatible with the speed environment.

Speed limits should be set so as to encourage, as far as practicable, a uniform speed of travel and hence reduce the potential for conflicts due to speed differentials between vehicles. Excessive variation among vehicle speeds can indicate either an

inappropriately set speed limit or that drivers’ perception of the speed environment is open to confusion. The second of these

causes may require corrective action other than reassessment of the speed limit.

2.1.2 General principles

2.1.2.1 Determining speed limits

The following recommendations and requirements apply when determining speed limits:

(a) Speed limits shall be capable of being practically and equitably enforced by use of speed zones of adequate length, by limiting speed limit changes, and by clarity and frequency of signposting.

Where the speed limit exceeds the maximum safe speed of travel due to an isolated geometric deficiency or hazard, advisory speed

signs displayed in conjunction with the relevant warning signs in accordance with AS 1742.2 shall be used to advise drivers of the desired speed.

(c) Speed limit signs on unsealed roads have traditionally displayed the default urban or default rural limit. Jurisdiction

supplements may provide guidance if other speed limits are to be permitted within that jurisdiction.

All signposted speed limits shall be in multiples of 10 km/h (except for a variation in South Australia that allows 25 km/h in

school zones and road work sites).

Recommended：