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BCU 460, BCU 465 · Edition 11.19
144
Glossary
23 .15 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.
from EN 13611/A2:2011
23 .16 Mean time to dangerous failure
MTTF
d
Expectation of the mean time to dangerous failure
from EN ISO 13849-1:2008