Table 9 Conditional probability formula of each safety barrier (Landucci et al., 2017)
From: Large-scale energy storage system: safety and risk assessment
Type | Safety barrier parameters | Outcome value | Description | Formula |
|---|---|---|---|---|
1 | Probability of failure on demand, PFD only | 0 | Activated successfully | \(P\left({E}_{i}^{n}\right)=1-PFD\) |
1 | Failed to activate | \(P\left({E}_{i}^{n}\right)=PFD\) | ||
2 | Probability of failure on demand, PFD & effectiveness, η | 0 | Activated successfully, effective mitigation | \(P\left({E}_{i}^{n}\right)=(1-PFD)(1-\eta\)) |
1 | Failed to activate | \(P\left({E}_{i}^{n}\right)=PFD\) | ||
2 | Activated successfully, ineffective mitigation | \(P\left({E}_{i}^{n}\right)=(1-PFD)(\eta )\) | ||
Any | Any | X | Path not considered within ETA sequence | \(P\left({E}_{i}^{n}\right)=1\) |