Crash sensors measure collision impact and transmit their signals to the central control unit. The occupant restraint systems are then  activated - or not - depending on the nature and severity of the impact. This prevents airbags from inflating if they would fail to provide  any protection because of the nature of the accident.

This system also cuts repair costs, as does the 'intelligent' airbag control unit that decides on its own, according to the severity of the  accident, whether the airbag needs replacement.

Vauxhall Astra has lap-and-shoulder safety belts for all seats with belt tensioners and force limiters - the front safety belts also have  height adjustment. A warning system checks whether the front-seat occupants are wearing safety belts. If the car is started without  the safety belts having been fastened, a flashing symbol appears on the instrument panel and there is an audible warning.

The optional seat occupancy identification system prevents the passenger front and side airbags from being triggered if the seat is  unoccupied or if the latest type of child's seat with a transponder is in use on the seat.

Rear seat mountings for an ISOFIX child's seat are supplied together with the child's seat identification system. Measures to protect  Astra's occupants include four standard head restraints. The risk of injury to the driver is also reduced by the safety Pedal Release  System (PRS), which releases the brake and clutch pedals in the event of an impact and protects the driver's lower legs and feet.

In addition, in a crash, the car's hazard warning flashers are switched on automatically when an airbag or seat belt tensioner is  triggered. The central locking system is released so that all the car's doors can be opened.


Rigid bodyshell

The extremely rigid, non-deforming bodyshell of the new Astra forms the foundation of the comprehensive safety package.

Compared with the previous Astra, bodyshell flexing resistance has been increased by 52 per cent and lateral flexing by a similar  amount. Torsional rigidity, the basis for accurate suspension tuning, is also improved by 15 per cent.

Passengers will also appreciate a reduction in vibration transmitted through the car body.

The car also uses more aluminium or high-strength steel (these now account for 52 per cent of the bare bodyshell compared with 44  per cent in the previous model). Its aerodynamic drag coefficient is cD = 0.32.


Load paths absorb impact energy In a frontal crash, the impact energy generated is absorbed by three load paths

The upper load path is the front end of the bodyshell, in which the energy is diverted through the wheel control struts to the A-pillars,  the door reinforcements and the roof.

The central load path consists of the body's main side members, which are extended back under the floor as far as the B-pillars and  the sills. The third load path consists of the hydroformed suspension subframe with additional triangular plates that dissipate energy  farther back into the underbody of the car.

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