Given a smart transmitter with a safe failures ratio of 60%, what is the Safe Failure Fraction?

Given a smart transmitter with a safe failures ratio of 60%, what is the Safe Failure Fraction?

• A. 0.7
• B. 0.6
• C. 0.42
• D. 0.88

Answer: (D)

The Safe Failure Fraction (SFF) is a critical metric in Functional Safety that quantifies the proportion of failures in a safety-related system that are deemed safe. It is calculated using the formula: \[ SFF = \frac{S}{S + D + H} \] where: - \(S\) refers to safe failures, - \(D\) refers to dangerous failures that are detected, - \(H\) refers to dangerous failures that are not detected. In the context of the problem, the safe failures ratio (SFR) indicates the percentage of failures that are safe out of all possible failures, which in this case is given as 60%. To determine the SFF, it is essential to understand that for systems classified under Functional Safety, the SFF must be significant enough to meet the requirements of safety integrity levels (SILs). If the safe failures ratio is 60%, this means that out of all failure occurrences, 60% are classified as safe. To calculate the Safe Failure Fraction, one would typically also need to consider the dangerous failures detected and undetected. However, since the provided answer indicates D is the correct choice, it suggests a high value of SFF above 0.6, indicating

The Safe Failure Fraction (SFF) is a critical metric in Functional Safety that quantifies the proportion of failures in a safety-related system that are deemed safe. It is calculated using the formula:

[

SFF = \frac{S}{S + D + H}

]

where:

• (S) refers to safe failures,

• (D) refers to dangerous failures that are detected,

• (H) refers to dangerous failures that are not detected.

In the context of the problem, the safe failures ratio (SFR) indicates the percentage of failures that are safe out of all possible failures, which in this case is given as 60%. To determine the SFF, it is essential to understand that for systems classified under Functional Safety, the SFF must be significant enough to meet the requirements of safety integrity levels (SILs).

If the safe failures ratio is 60%, this means that out of all failure occurrences, 60% are classified as safe. To calculate the Safe Failure Fraction, one would typically also need to consider the dangerous failures detected and undetected. However, since the provided answer indicates D is the correct choice, it suggests a high value of SFF above 0.6, indicating