Redundant and diverse systems are used in safety design to enhance safety by

• A. Provide backup functionality through identical copies and/or different physical principles to perform the same function
• B. Eliminate human operators from safety systems
• C. Reduce the number of sensors used in safety systems
• D. Ensure only one path to safety exists at any time

Answer: (A)

Redundancy and diversity in safety design build resilience by making sure the safety function can operate even if some parts fail. This is achieved by having backup copies that can take over (redundancy) and by using different physical principles to perform the same safety function (diversity), so a single fault or a common failure mode doesn’t disable all paths. Because of this, the system remains capable of ensuring safety even under adverse conditions.

This approach aligns with providing backup functionality through identical copies and/or different physical principles to perform the same function. The other ideas don’t contribute to that resilience: removing human operators isn’t about creating backup paths, reducing sensors lowers the ability to detect issues, and having only one path to safety introduces a single point of failure.