In order to produce a safing concept, an extra-safing-sensor in the control unit (ECU) is foregone and the safing function from one of the available acceleration or turn-rate sensors (S1 to S5) is replaced. Furthermore a pre-stage is connected to the firing element (Z1, Z2), before the existing firing path, which, depending upon the sensor signals as analysed by the controller unit (1), controls a safety switch (T11), in series with the firing switches and the firing element.