Flexible road safety barriers catch vehicles before they hit something harder – like a pole, tree or oncoming car.
Flexible road safety barriers are installed down the middle of a road to prevent head-on collisions or along the side of the road to help stop run-off-road crashes.
If you hit a flexible barrier, the steel cables flex, slowing down your vehicle and keeping it upright. The barriers absorb the impact of the crash so you and the people with you, don't.
They’re a cost-effective infrastructure treatment that can reduce the number of people killed or seriously injured in crashes by 75 percent.
Motorcyclists have less protection in the event of a crash.
Roadside and median flexible safety barriers are highly effective in preventing deaths and injuries for all road users including motorcyclists.
We’re investing in improved roads and roadsides that are safer for motorcyclists. Motorcyclists are more likely to survive an impact with a flexible road safety barrier than an impact with trees, poles or oncoming vehicles which the barrier will prevent them striking in a crash.
The University of New South Wales has undertaken an in-depth analysis of motorcycle impacts into roadside barriers in both New Zealand and Australia. The data shows that barriers of any kind contributed to a very small percentage of motorcycle fatalities.
A study of the NZ motorcycle-barrier crash data from January 2001 to July 2013 shows of 20 motorcycle fatalities sustained as a result of riders hitting a roadside or median barrier, just 3 involved flexible safety (wire rope) barriers, while 13 involved traditional steel ‘W’ beam barriers and 4 other barrier types. Over the same time period there were 97 motorcyclist fatalities from collisions with posts or poles, 70 from hitting traffic signs and 93 from crashing into unprotected trees.
Median barriers can create challenges for over-dimension loads. While median barriers don’t restrict the ability for over-dimension loads to move through, heavy vehicle operators need to plan their journeys to ensure safe navigation of median barriers.
This video explains how median barriers work, how they are maintained and how access for over-dimension vehicles and maintenance activities can be safely managed.
With the introduction of median barriers, turnaround facilities will be provided to support right turn movements at safe locations.
While people will need to drive a bit further, turnaround facilities will provide a much safer right turning access off and on to the road for people. Specifically, they can:
Turnaround facilities also optimize the operation of median barriers by reducing the number of breaks in the barrier for access, which reduces likelihood of crashes caused by people crossing the centreline.
The design of turnaround facilities, and the distances between these facilities, is determined by the road environment and expected users.
There are a hierarchy of turnaround facility options to support the introduction of median barriers, for example:
A combination of turnaround facilities on a road where there are median barriers is likely.
Turnaround bays, such as jug handles, are going to become more common. They can be located on a state highway or on connecting local roads.
The video below shows how people can use a turnaround bay on a state highway.
More information on turnaround facilities can be found on the Road to Zero, Speed and Infrastructure Programme Design Framework page:
3.5kms of flexible median barriers were installed on SH1 Centennial Highway, just north of Wellington, in 2005. This was a treacherous piece of road – in the 4 years to 2000 it recorded 8 fatalities, 2 serious injuries and 7 minor crashes.
In the four years from 2005 to 2009, following the installation of the flexible median safety barrier and lowering the speed limit to 80kph, there were no fatal and no major injury crashes, and just 3 minor injuries recorded.
Between 2005 and October 2015, the Centennial Highway barrier has been hit over 100 times without a single death
The construction of flexible road safety barriers on SH1.
Building more flexible barriers to save lives on our country roads(external link) - Monash University, 6 August 2018
