Lay-bys and protection against lateral obstacles in tunnels

Vehicle collisions involving lay-bys or other lateral obstacles in tunnels are fortunately a relatively rare occurrence. However, the consequences of such a collision are extremely severe and more often than not result in fatalities. The most dramatic example of this is the accident which occurred in the Sierre tunnel in Switzerland in 2012, when the collision of a coach with the back-wall of a lay-by caused the death of 28 passengers, including 22 children.