Besondere Merkmale (BM) - Significant and critical characteristics (SC)
Product features or production process parameters with direct influence on one of the factors safety (S), homologation (H) or function (F).
Conversely, one can say that if a feature marked as SC fails you may assume an interference of at least one of the parameters S, H or F. Concerning a product feature not identified as SC, one could therefore assume that a deviation from the specified tolerance range does not necessarily cause the failure of a whole function, the violation of a homologation relevant criterion or a direct safety risk.
Taking the example of a night light automatic, the light sensor would be classified as SC-S (characteristic feature with influence on safety), provided the control unit logic reads: “Light on if the sensor reports darkness”. In that case it would be possible to bypass the safety relevance for the component light sensor by changing the control unit logic to: “Light always on, unless the sensor unequivocally reports brightness.”
All SCs need special attention during production, quality control and with regard to the required field quality. Therefore, they produce higher expenditures than the parameters that are not classified as SCs and need special marking in technical drawings and for the production process. Thus, the product development's basic objective is to reduce the number of the resulting SCs to a minimum in order to minimize the costs and the risk of critical quality defects.