9
C1
F1
F1
F2
F2
C2
C3
C4
P1
P1
P2
P2
W3 W2 W1
― ― ―
SIL 1 ― ―
SIL 1 SIL 1 ―
SIL2 SIL 1 SIL 1
SIL3 SIL2 SIL 1
SIL3 SIL3 SIL2
SIL4 SIL3 SIL3
SIL4 SIL4 SIL3
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Risk-graph and requirement classes
according to: IEC 61 508 / 61 511
C= Extend of damage
C1: slight injury of a person
C2: severe, irreversible injury of one
or several persons
C3: death of several persons
C4: catastrophic implication with many
persons death
F= Duration of stay
F1: rarely or more often
F2: frequently up to permanent
P= Hazard prevention
P1: possible under certain conditions
P2: rarely possible
W= Probability with which undesirable
incidents happen
W1: very low
W2: low
W3: relatively high
= No safety requirement
24011
NAMUR
& Inline
98015
NAMUR
& Inline
24010
NAMUR
& Inline
