A safety instrumented function with a risk reduction factor of 70 corresponds to which SIL?

A safety instrumented function with a risk reduction factor of 70 corresponds to which SIL?

• A. SIL1
• B. SIL2
• C. SIL3
• D. SIL4

Answer: (A)

To understand which Safety Integrity Level (SIL) corresponds to a safety instrumented function with a risk reduction factor of 70, we can refer to the definitions and requirements for the different SILs as per relevant standards like IEC 61508. SILs are categorized from SIL1 to SIL4, with each level representing a range of risk reduction factors (RRF) that a safety function must achieve. The RRF is indicative of how effectively a safety function can minimize risk. The RRF required for each SIL is as follows: - SIL1 requires a risk reduction factor between 1 and 10. - SIL2 requires an RRF between 10 and 100. - SIL3 requires an RRF between 100 and 1,000. - SIL4 requires an RRF of 1,000 or greater. Given that a risk reduction factor of 70 falls between 10 and 100, it aligns with the criteria for SIL2. Therefore, this means the correct classification for a safety instrumented function with a risk reduction factor of 70 would be SIL2, not SIL1. Choosing SIL1 would imply a much lower risk reduction capability than the function indeed provides. Hence, SIL2 is the appropriate

To understand which Safety Integrity Level (SIL) corresponds to a safety instrumented function with a risk reduction factor of 70, we can refer to the definitions and requirements for the different SILs as per relevant standards like IEC 61508.

SILs are categorized from SIL1 to SIL4, with each level representing a range of risk reduction factors (RRF) that a safety function must achieve. The RRF is indicative of how effectively a safety function can minimize risk. The RRF required for each SIL is as follows:

• SIL1 requires a risk reduction factor between 1 and 10.

• SIL2 requires an RRF between 10 and 100.

• SIL3 requires an RRF between 100 and 1,000.

• SIL4 requires an RRF of 1,000 or greater.

Given that a risk reduction factor of 70 falls between 10 and 100, it aligns with the criteria for SIL2. Therefore, this means the correct classification for a safety instrumented function with a risk reduction factor of 70 would be SIL2, not SIL1.

Choosing SIL1 would imply a much lower risk reduction capability than the function indeed provides. Hence, SIL2 is the appropriate