Run Off Road
Run-off-road crashes are common, especially in high speed areas. They occur at bends and on straight sections of road. In high speed environments they can have severe outcomes, particularly if an object is hit (for example trees, poles, pedestrians) or there is a steep embankment or cliff.
Research shows that the survival rate for hitting an object head-on reduces dramatically above 70 km/h, while a side impact into a pole or tree is greatly reduced at speeds above 40 km/h. Therefore, the consequences of running off the road above this speed will often be severe.
There are a number causes for this crash type, including:
- driver fatigue
- impairment (including alcohol, drugs, and use of medication)
- speeding
- avoiding hazards on the road.
There are also a number of road related features that contribute to a higher incidence of run-off-road crashes, including:
- presence of road curves (especially where they are unexpected, or their severity is greater than expected)
- narrow or no road shoulder
- poor road surface condition
Engineering treatments generally act to assist drivers to stay on the road (e.g. improvements to the road surface, advanced information about curves and their severity), alert drivers that they are leaving the road (e.g. rumblestrips), improve the chance of recovering control of the vehicle if it does leave the road (e.g. shoulder treatments), or reduce the severity of the outcome if a vehicle does leave the road (e.g. clear zones and crash barriers).
- Safer Roads
- Estimated cost
- Casualty Reduction
- Delineation
- Low
- 10-25%
- Rumble Strips
- Low
- 10-25%
- Skid Resistance
- Low to medium
- 25-40%
- Roadside Safety - Hazard Removal
- Low to medium
- 25-40%
- Sideslope Improvement
- Medium
- 10-25%
- Roadside Safety - Barriers
- Medium
- 40-60%
- Shoulder Sealing
- Medium
- 25-40%
- Speed Management
- Medium
- 25-40%
- Traffic Calming
- Medium to high
- 25-40%
- Lane Widening
- Medium to high
- 25-40%
- Median Barrier
- Medium to high
- 60% or more
- Realignment - Horizontal
- High
- 25-40%
- Realignment - Vertical
- High
- 10-25%
- Safer Vehicles
Safer Roads
- Safer Roads
- Estimated cost
- Casualty Reduction
- Delineation
- Low
- 10-25%
- Rumble Strips
- Low
- 10-25%
- Skid Resistance
- Low to medium
- 25-40%
- Roadside Safety - Hazard Removal
- Low to medium
- 25-40%
- Sideslope Improvement
- Medium
- 10-25%
- Roadside Safety - Barriers
- Medium
- 40-60%
- Shoulder Sealing
- Medium
- 25-40%
- Speed Management
- Medium
- 25-40%
- Traffic Calming
- Medium to high
- 25-40%
- Lane Widening
- Medium to high
- 25-40%
- Median Barrier
- Medium to high
- 60% or more
- Realignment - Horizontal
- High
- 25-40%
- Realignment - Vertical
- High
- 10-25%
Safer Vehicles
- Safer Vehicles
Safer People
- Safer People
Did you know?
Sealed shoulders reduce the chance of 'overcorrection' and head on crashes.
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