Roof rails are subject to many demanding tests. For example, their corrosion resistance, load-bearing capacity, strength and service life in various conditions are verified. The subsequent watertightness of the vehicle after the installation of roof rails is also tested. In City Crash tests, roof rails carrying a weight of 90 kg must remain on the body even during the simulation of an impact associated with a force of approximately 12 G lasting for 50 milliseconds.