The standard EuroNCAP testing procedure requires a 40mph (64km/h) frontal crash test speed, and performance at that level is the basis for the tested car's rating. However, Germany's ADAC testing body wanted to find out what happens if the speed is raised just 10mph (16km/h) to 80km/h (50mph), and did so by testing the Renault Laguna sedan, a top performer in the standard tests. The results are surprising.

Raising the speed by just 10mph (16km/h) resulted in nearly 50% more energy to be dissipated by the car's crumple zones, effectively exceeding their capacity. The increased energy resulted in a significant increase in risk of injury to all occupants, especially the driver, reports Autobild. The testing showed that the driver's chest impacted the steering wheel despite the use of seatbelt and airbags due to the added speed, while the crumpling body of the car pushed the dashboard into the driver's knees, risking injury there as well.

The front-seat passenger fared better, with the Laguna's soft plastics minimizing the damage of the dummy's head striking the dashboard despite the presence of an airbag and being seat-belted in as well. The child-sized dummies in the rear seat showed increased risk of injury, but due primarily to the increased force with which they were thrown against the restraints.

All of this was from testing of a car that scored a full five-star rating in the 40mph (64km/h) EuroNCAP testing procedure, which is as rigorous as any in the world. The same speed is used in U.S. by the IIHS, while the NHTSA uses a speed of just 35mph (56km/h) in their testing programs, highlighting the potential for cars around the world to require revised accident ratings that more accurately reflect real-world speeds, and also illustrating the effect speed has on the force of an accident.

The ADAC recommends wider application of active safety equipment such as traction control and braking aids to help avoid accidents and reduce speeds when accidents are unavoidable as the most realistic way to reduce the risk of high-speed travel. Sufficiently strengthening a car to withstand high-speed collisions is likely not practical due to manufacturing, costs and fuel-efficiency considerations.