HOW DOES IT WORK?

In any kind of crash — be it head-on, from the rear, or sideways — the driver’s main mass area, the body, is decelerated by the harness. However, appendages such as your arms; legs; and, most important, your head maintain velocity until they’re decelerated by the connecting joints. In the case of the head, that’s your neck (and, by extension, spine). The HANS device is tasked with maintaining the head’s relative position to the body by anchoring it within a safe range of movement — while still allowing the wearer to otherwise move their head as normal — preventing the neck from exceeding its normal range of articulation, which causes severe injury and death. It also transfers that force to the much stronger collar bone area, dissipating it into the torso, shoulders, harness, and seat connections as the head is decelerated.

Typically constructed out of carbon fibre, a HANS device is shaped like an upside-down ‘U’ that slots over the back of the neck with each arm running down over the driver’s collarbone and covers the pectoral area. The driver’s shoulders support the device, although the only place in which the device is physically connected to the wearer is through the helmet anchorages. The device is only able to be used with compatible helmets that have these anchorages, which serve one of the most important functions of the device — anchoring the head to the driver’s body to protect the neck at the base of the skull.

Used only in conjunction with harnesses that are four-point and upwards, the device is held down by the two vertical straps that pass over it as they head downwards over the driver’s shoulders to be connected at the waist. Therefore, the HANS device is secured to the body of the driver, not the seat, and also aids the effectiveness of the shoulder straps by bringing them closer together for improved protection.

The HANS manual also makes a point of mentioning that, to function correctly, the device should never touch the helmet or the headrest, requiring a minimum clearance of 40mm.

Testing has shown that HANS devices can reduce head movement in a crash by up to 44 per cent, the force applied to the neck by up to 86 per cent, and the acceleration applied to the head by up to 68 per cent — meaning that even big impacts will produce figures under the injury threshold when the HANS device is in use. That’s pretty staggering when you consider how much force is experienced when going into the wall even at low speeds.