For safety critical systems, the fundamental concern is the ability to avert accidents from occurring.
Even low failure likelihoods for software products are not tolerable in such systems if these failures may lead to accidents. Consequently, in addition to the quality assurance activities, different particular methods are also used for safety critical systems based on analysis of hazards, or logical pre-conditions for accidents:
Both hazard control and damage control are post-failure activities that attempt to include the defects so that they will not lead to accidents or the accident damage can be controlled or minimized.
These activities are important to safety critical systems, which are not commonly covered in the quality assurance activities for other systems.
A lot of methods for software bug averting, decrease, and tolerance may be used in safety-critical systems for hazard removal and decreases through focused activities on safety-critical product elements or features.