8.5.2 LUMS Applications
LUMS signs are traffic control devices with a regulatory function. These include:
- lane open and speed limit
- merge left, right or both
- lane closed
- exit lanes
- designated turning lane.
Refer to Austroads (2019d) for details. Additional symbols may be used to indicate the use of a lane by a priority vehicle type, such as buses, high occupancy (T2/T3 vehicles) or trucks. Any other symbols used should be supported by the jurisdictional version of the Australian Road Rules.
There are a number of different LUMS applications that contribute to smart motorway benefits. LUMS applications enable reactive management of traffic in response to an incident, event, inclement weather and other causes of non-recurrent congestion. LUMS is also used to provide capacity improvement by enabling operational strategies involving use of the emergency lane for traffic.
LUMS for incident and event management
Once an incident is verified, LUMS can be used to quickly and safely activate traffic management devices (LUMS signs) that will close one or more lanes and manage traffic speed on approach to and through the incident site.
The reduced speed limit improves safety for lane-changing manoeuvres and provides safer conditions at the incident site for the benefit of workers, incident victims and the travelling public. Lane control can be used to improve emergency access to the incident site, as well as to divert traffic off the motorway via an exit ramp in the case of a full carriageway closure or major incident/event.
Lane control and speed limit reductions may also be triggered by planned road works/maintenance activities or other events.
LUMS for capacity increase (i.e. emergency lane use)
LUMS is a critical component of any operational strategy that allows full or part-time use of the emergency lane in order to increase motorway capacity. In the absence of an emergency lane, LUMS is required to provide operators with a means to quickly and safely close lanes to protect an incident site if a crash occurs, and to enable emergency access. Further details on operational strategies involving the absence of an emergency lane or use of the emergency lane as a running lane is provided in Section 8.6.