All Saab 9-3 and 9-5 models have now achieved top marks for protection against neck injury following the latest round of rear-end collision tests conducted by the Thatcham insurance research center in the United Kingdom. All are fitted as standard with Saab Active Head Restraints (SAHR).

The Thatcham test classifies the performance of a car's front seats and head restraints in offering neck injury protection as 'Poor', 'Marginal', 'Acceptable' or 'Good'. The Saab 9-3 Convertible, 9-3 SportCombi and 9-5 models have now been awarded the best-possible 'Good' rating, as achieved last year by the 9-3 Sport Sedan in the first round of tests.

A static evaluation of seat design is carried out first, where the position of the head restraint relative to an occupant's head is measured on a crash test dummy representing a mid-sized, male adult. A dynamic test is then performed with the seated dummy mounted on a sled, which is accelerated to 16 kph ( 10 mph ) in 0.1 seconds to simulate the effect of a typical low speed rear-end collision.

The SAHR has been developed to reduce relative movement between the head and lower back. The restraint is mounted at the top of a frame, inside the seat-back, which is designed to pivot at its mid point.

In a rear-end impact, the occupant’s lower back is forced rearwards by inertia against the bottom portion of the seat-back. A mechanical linkage in the frame then forces the upper half, carrying the head restraint, upwards and forwards to catch the occupant’s head and help minimize the amount of whiplash movement. After activation, the SAHR immediately returns to its passive position, ready for further deployment.