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. These barriers catch vehicles before they hit something harder, like a pole, tree or oncoming car.
If you hit a flexible barrier, the steel cables flex, slowing down your vehicle and keeping it upright. They absorb the energy of the impact, which means that you and your passengers don’t.
When safety barriers are installed along the side and centre of the road, they can reduce the number of people killed or seriously injured in crashes by 75 percent.1
Watch the video on how median barriers work.
If you ride a motorcycle, you are at a higher risk of being seriously injured or killed on our roads, as you’re more vulnerable in a crash.
Many people who are injured or killed while riding a motorcycle are struck by vehicles where the driver has lost control and, in some circumstances, crossed the centre line. Studies in Sweden show flexible median barriers can reduce the number of motorcyclists killed by up to 50 percent.2
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.
This video shows installing flexible median barriers on high speed, high volume stretches of road will make a real difference to people travelling on them including motorcyclists.
Maintaining median barriers is an important part of ensuring they continue to reduce deaths and serious injuries.
This video shows how these safety barriers are maintained to ensure they continue to keep everyone safe.
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. Specifically, they can:
Turnaround facilities also optimise the operation of median barriers by reducing the number of breaks in the barrier for access. Fewer breaks mean fewer crashes caused by people crossing the centreline.
There are a different turnaround facility options to support median barriers, depending on the road environment and the way people are using the road. Some examples include:
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 here:
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 four years to 2000 it recorded eight fatalities, two serious injuries and seven minor crashes.
Between 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 three 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.
Report to the Minister of Transport on median barriers – July 2016(external link)
Building more flexible barriers to save lives on our country roads(external link) - Monash University, 6 August 2018
Download print resources for flexible road safety barriers:
Standard safety intervention resources
1 Standard Safety Intervention Toolkit, published September 2021, Waka Kotahi NZ Transport Agency.
2 Arne Carlsson (2009). Evaluation of 2+1 roads with cable barriers: Final report(external link), Swedish National Road and Transport Research Institute. VTI rapport 636A.
