2017-09
28
Functional Safety HiD2022*, KFD2-STC5-(Ex)*, KFD2-STV5-(Ex)*
List of Abbreviations
7 List of Abbreviations
ESD Emergency Shutdown
FIT Failure In Time in 10
-9
1/h
FMEDA Failure Mode, Effects, and Diagnostics Analysis
s
Probability of safe failure
dd
Probability of dangerous detected failure
du
Probability of dangerous undetected failure
no effect
Probability of failures of components in the safety loop that have
no effect on the safety function. The no effect failure is not used
for calculation of SFF.
not part
Probability of failure of components that are not in the safety loop
total (safety function)
Safety function
HFT Hardware Fault Tolerance
MTBF Mean Time Between Failures
MTTR Mean Time To Restoration
PCS Process Control System
PFD
avg
Average Probability of dangerous Failure on Demand
PFH Average frequency of dangerous failure
PTC Proof Test Coverage
SFF Safe Failure Fraction
SIF Safety Instrumented Function
SIL Safety Integrity Level
SIL (SC) Safety Integrity Level (Systematic Capability)
SIS Safety Instrumented System
T
1
Proof Test Interval
Functional Safety HiD2022**, KFD2-STC5-(Ex)*, KFD2-STV5-(Ex)*