BMW has developed a vital new occupant safety feature, Crash-Activated Headrests, a further development of the BMW Active Headrestraints currently in use.

Now fitted as standard to BMW 6 Series, 5 Series, X5 and X3, these newly developed headrests significantly reduce the risk of cervical vertebra injury in the event of a rear-end collision.

Controlled by the car’s safety electronics, the Crash-Activated Headrests move forward towards the occupant’s head by up to 60 mm, and upwards by as much as 40 mm in a split second, after a rear-end collision is detected. The aim is to reduce the gap between the headrests and the occupant’s head before whiplash injury can occur.

The cervical vertebra (CV) syndrome (effectively over-stretching the occupant’s cervical vertebrae) is also referred to as whiplash trauma. It is one of the most common types of injury in traffic accidents and is caused by sudden impacts from behind.

Highly painful in many cases, such a trauma may be encountered in rear-end shunts at even relatively low speeds in city traffic. To avoid collisions of this kind, BMW introduced two-stage brake lights back in 2003, the illuminated area of the brake lights becoming larger whenever the driver applies the brakes particularly hard, thus giving following motorists an early warning that they too must brake hard, or seek an escape route to avoid an impact.

Now, new Crash-Activated Headrests offer the occupant of a BMW additional protection whenever a collision is unavoidable.

Crash-Activated Headrests can be clearly distinguished through their modern, two-piece look, formed by the headrest support and the impact plate. A button is let into the side of the padded section to allow for manual adjustment of headrest depth, in the interests of enhanced driving comfort. This allows the occupant to vary the position of the padding within three different levels by up to 30 mm.

In a collision, the impact plate together with the padding will instantaneously move forward by up to 60 mm, reducing the gap between the headrest and the occupant’s head. And at the same time the impact plate and padding will move up by up to 40 mm.

Within the Crash-Activated Headrest, a complex, spring-driven mechanical operating unit is activated by a pyro-actuator. As soon as the pyro-actuator ignites, it releases spring-loaded plates that move the impact plate and the headrest padding forward and upward.

The pyro-actuator receives its ignition signal from the airbag control unit as soon as the sensors detect a relevant impact at the rear of the car.

This system was developed by BMW and acts very quickly and efficiently to protect the occupants from whiplash trauma and potential injury.

The new Crash-Activated Headrests enhance not only the stabilising and safety functions of the headrest, but also the level of comfort while driving. Conventional headrests set to the right position are often perceived as too close to the occupant’s head and therefore appear to limit their freedom of movement. The new crash-activated headrests, in turn, provide not only enhanced safety, but also an improved feeling of space, since they are not required to rest directly on the occupant’s head while driving.

Once the safety mechanism in the Crash-Activated Headrests has been actuated, a Check/Control message will appear in the instrument cluster reminding the driver to have the pyro-actuator replaced at an Authorised BMW Dealer.