Key factors of safety analysis for application software in vital computers

Vital computers play a fundamental role in the safety-critical industrial applications. It is necessary to conduct functional safety analysis against its application (logic) software to guarantee the functionality of the whole system to reach the domain-requested safety integrity level. However, the diversity of application software brings difficulty to the conduction of safety analysis with a high quality. In this paper, the key factors for functional safety analysis against the application software within such system are proposed. The deduction of such key points brings benefits for understanding the common factors that affect the functional safety of the application, and thus the safety-related bottleneck within such software can be discovered and resolved with more effectiveness. The conclusions of this paper can also be applied as a guidance for the manufacturers of the safety-critical programmable system products to establish a normalized and procedural functional safety analysis against the safety-critical software.