Which document outlines the required functions of safety systems?

• A. System Architecture Document.
• B. Safety Requirements Specification.
• C. Functional Safety Assessment.
• D. Operational Safety Plan.

Answer: (B)

The Safety Requirements Specification is the document that specifically details the required functions of safety systems. This document serves as a key component in the functional safety lifecycle, as it defines the safety functions that must be implemented to achieve the desired level of safety for the system. It typically includes specific requirements related to the safety functions, safety integrity levels (SIL), and performance requirements that the safety system must meet to mitigate risks associated with potential hazards.

In the context of functional safety, having a well-defined Safety Requirements Specification is crucial because it ensures that all stakeholders have a clear understanding of what the safety system needs to accomplish. This document acts as a foundation for the design, implementation, and verification processes, ensuring that all safety functions are accounted for and systematically addressed throughout the development lifecycle.