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TC · Edition 08.17
54
Glossary
10 .7 Probability of dangerous failure PFH
D
Value describing the likelihood of dangerous failure per
hour of a component for high demand mode or con-
tinuous mode. Unit: 1/h
see EN 13611/A2
10 .8 Mean time to dangerous failure MTTF
d
Expectation of the mean time to dangerous failure
see EN ISO 13849-1