Barriers are commonly seen on motorways, dual carriageways and other important roads in the UK, lining the boundaries of the road and the central reservation to prevent accidents. Regulations state that they should be a minimum of 30 metres in length when leading up to a hazard although with bridges and other settings where there is a risk of falling they need to be considerably longer. There are many different types of barrier available but they should be 0.61 metres in height to the middle of the beam.
All of the motorway barriers used in the UK have to be in compliance with European Standards EN1317. This means they are tested against a long list of criteria to ensure they provide the right level of protection. Standard containment barriers are checked with crash tests using a 1.5 tonne vehicle travelling at 70mph and hitting the barrier at a 20 degree angle. High containment barriers (those specifically designed for larger commercial vehicles) are tested with a 38 tonne vehicle travelling at 40mph and a 20 degree impact angle.
The different types of barrier used in the UK include large concrete ones, steel beam Armco style and steel wire variations. These encompass both rigid and flexible systems respectively. The choice of which one to use depends on the situation and the setting. When leaving the road could cause a fatal injury sturdy systems are used to prevent this from happening. When there is space for containment and run off the flexible ones offer great containment.
Motorway barriers are amongst the most important safety features of roads in the UK. They protect millions of motorists every year, preventing vehicles from colliding with oncoming ones and leaving the road. Developers are also looking at the potential for making barriers more acoustically insulated, reducing the noise and disturbance caused by busy roads.