Definition(s)
Immediately Revealed Failure
overt failure
detected failure
evident failure
failure which is immediately evident to operations and maintenance personnel as soon as it occurs
Note 1 to entry: The immediately revealed failures show themselves immediately, but the hidden failures which
are quickly detected by specific diagnostic tests are generally considered as immediately revealed failures.
Note 2 to entry: The repair of immediately revealed failures may begin immediately after they have occurred.
Note 3 to entry: The failures which are detected by periodic tests are not considered as immediately revealed failures.
Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global Standards