After the deaths of several high profile racers the world over had died neck injuries caused during a crash, the various world motorsport governing bodies gradually mandated the use of a Frontal Head Restraints (FHR) system. The most well known device are the HANS (Head and Neck Support).
The Fédération Internationale de l’Automobile (FIA) is generally accepted as being the world governing body for all motorsport (we exclude North America from that statement) and the FIA defines the specifications and lists the approved products relating to the safety aspects (helmets, race suits etc). The standard by which the main FHR component and the auxiliary components must comply is 8858-2010.
The purpose of the device is to keep the head from whipping forwards and backwards in a crash, without otherwise restricting movement of the neck. The device maintains the relative position of the head to the body, in addition to transferring energy to the much stronger chest, torso, shoulder, seatbelts, and seat as the head is decelerated.
The devices work by attaching the drivers helmet to the neck support that is held in place by the racing harness. Today there are several different types of neck support system available with the 2 most common being the HANS and Hybrid.
There are two main differences between the two types and these are described below:
The HANS system is connected to the drivers helmet using one tether on each side. This reduces the forward movement of the head but does not restrict the sideways or lateral movement of the head.
The hybrid system has two tethers on each side and thus restricts the head movement forwards and laterally.
The HANS device is held in place by the racing harness should belts over the shoulder support.
The hydrid device is held in place by straps around the drivers body and by the racing harness should belts.
All of the teams drivers use the HANS device. The lack of lateral support that is provided by the Hybrid system has been off-set through installing a seat with side wings which limit the lateral movement of the head.
In tests HANS was shown to reduce typical head motion in an accident by 44 percent, the force applied to the neck by 86 percent and the acceleration applied to the head by 68 percent – bringing the figures for even large impacts under the ‘injury threshold’.
The effectiveness of the HANS device was proven by a good friend of the team when he crashed into the side of another car at 130mph after his brakes failed. The driver simply undid his belts and got out the car un-aided. Other than a slight stiffness in his neck the driver suffered no injuries.