SIL Verification Calculator
Calculate PFDavg, RRF, and determine Safety Integrity Level based on IEC 61508/61511.
1. SIF Component Inputs (PFD)
Probability of Failure on Demand for Sensors
Probability of Failure on Demand for PLC/Logic
Probability of Failure on Demand for Valves/Actuators
2. Safety Requirements
The maximum allowed PFD to meet safety goals.
Achieved
--
Safety Integrity Level
RRF
--
Risk Reduction Factor
SIL Ratings (IEC 61508 / 61511 Low Demand)
| SIL | PFD Range (avg) | RRF Range |
|---|---|---|
| SIL 4 | \( \ge 10^{-5} \text{ to } < 10^{-4} \) | 10,000 - 100,000 |
| SIL 3 | \( \ge 10^{-4} \text{ to } < 10^{-3} \) | 1,000 - 10,000 |
| SIL 2 | \( \ge 10^{-3} \text{ to } < 10^{-2} \) | 100 - 1,000 |
| SIL 1 | \( \ge 10^{-2} \text{ to } < 10^{-1} \) | 10 - 100 |
Detailed Calculations
Enter values and click "Calculate Results" to see the breakdown.
Disclaimer: This tool is to check if the available SIF is adequate to meet the tolerable Risk rate or not. It assumes the user has already calculated the PFD values based on the selected architectures (i.e., 1oo1, 1oo2, etc.) considering all the factors like Proof testing intervals, Beta factor, CCF, etc.