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Table 3.
PFD for a high demand system.
| SIL | Probability of failure on demand (PFD/year) |
|---|---|
| 1 | > 10–6 to < 10–5 |
| 2 | > 10–7 to < 10–6 |
| 3 | > 10–8 to < 10–7 |
| 4 | > 10–9 to < 10–8 |