Traffic Barrier
A traffic barrier barricades vehicles so that if a vehicle gets off course, it protects the other vehicles from this vehicle. You may find a barrier between a highway, or just in your local town because of a big road project.
Traffic barriers can be concrete, plastic, filled with water or filled with sand. One type of traffic barrier is called a ‘jersey style’ barrier, presumably because they were commonly used in jersey. They are designed with many specs for tests in mind so many reach all specs necessary.