756-757 / 973
Proof Testing – What does IEC 61508 / 61511 say?
IEC 61508-6 / 3.8.5 / Edition 2
Proof Test:
Periodic test performed to detect dangerous hidden failures in a safety-related
system so that, if necessary, a repair can restore the system to an “as new”
condition or as close as practical to this condition IEC 61508-4 / 3.8.5 /Edition
2].
IEC 61511-1 / 3.2.58
Proof Test:
Test performed to reveal undetected faults in a safety instrumented system so
that, if necessary, the system can be restored to its designed functionality