availability

A component of a safety-related system is available, if it is ready in all cases of required operation it has been designed for, e.g. to control design basis accidents, to prevent impermissible plant conditions or impermissible loads of components and systems, and if its functionality has been demonstrated by periodic inspections (cf. definition "periodic inspections"). Non-availabilites of components or systems, which are induced temporarily and in a planned manner by procedures as specified in the operating manual, are not reportable if this is also considered in the safety specification of the operating manual.