Virtually no other area inspires Mercedes-Benz engineers more than researching new safety technologies. They passed their first key safety milestone as early as the 1950s with the development of the passenger safety cell, invented by Béla Barényi. Today it is one of numerous elements of an integrated safety concept that edges Mercedes-Benz vehicles closer to our vision of accident-free driving.

Most accidents start long before the actual collision: with a lapse in concentration, poor visibility or an unanticipated hazard. So we have fitted the C-Class with innovative safety and assistance systems which promote relaxed motoring and help the driver to bring critical situations under control.

The optionally available PRE-SAFE® occupant protection system can detect critical handling situations and if necessary preventively activate reversible safety systems which help to reduce the risk of injury to the vehicle occupants. To do this, PRE-SAFE® continually monitors the sensor data from systems such as the ESP® and BAS, and it can recognise, for instance, vehicle understeer or oversteer as well as emergency stops.
If the typical characteristics of a critical driving situation are identified, safety systems can respond within a fraction of a second. The motor-driven belt tensioners are activated, the electrically adjustable front-passenger seat with (optional) Memory Package is moved to a more "favourable" crash position, and the side windows and (optional) sliding sunroof are closed automatically.

Numerous occupant protection systems can significantly reduce the risk of injury during an accident. Examples include the NECK-PRO head restraint, a standard feature on the front seats: when the sensor detects an impact from the rear, it thrusts the head restraint forward and upward in a matter of milliseconds to reduce the gap between it and the occupant's head.
The C-Class is also equipped with adaptive belt tensioners for the front seats, belt tensioners for the outer rear seats and with numerous airbags, including two-stage driver/front-passenger airbags, front sidebags (rear sidebags are optional), driver kneebag, and windowbags extending across all seat rows. The windowbag protection zone covers virtually the entire area of the side windows.
The sidebags and windowbags are controlled by pressure sensors: if the door deforms due to a side impact, the air pressure between the door panelling and the interior of the door increases. This change is registered by the sensors, which help the control system to trigger the airbags.
Protection also extends to other road users, however, thanks to features such as smooth body surfaces with a generous degree of predefined yield.