HANS System

The HANS system (Head And Neck System) is compulsory to all F1 drivers since 2003 and just appears in the WRC championship.
In case of violent accidents, the HANS systems help to prevent serious damages to the vertebral column provoqued by the whiplash on a head which is not retained. This is the result of a brutal deceleration when the car collides with an obstacle. Violent movements of the head can break the neck and/or irreversibly damage the brain and the vertebral column nerves. The HANS system aim is pretty simple: it's nothing more than a support to whom are bound straps, at the rear part and on each side of the helmet. The straps length is adjusted to ensure to the driver a limited mobility of the neck. 
Naturally, the drivers' helmets and also bucket seats and harnesses were redesigned because of their new attach points to be compatible with the HANS safety system.
The FIA 8858-2002 norm dedicated to HANS, was established to guarantee an optimised resistance during strong decelerations. 

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