A comprehensive programme has been developed covering cables themselves (control and power), terminations, penetrations, junction boxes, panels and associated termination. Such a programme would include the effects of normal ageing as well the effects of design basis events for which relevant cable systems have to be qualified to meet the design requirements. It should be noted that PLiM ageing assessments of these components need to be integrated with Environmental Qualification programmes, where the cable system components have a safety function. Also extensive condition assessment studies of cable systems have been performed as part of PCA studies and are useful for LTO.

Results from these programmes will determine the extent, if any, of remedial work such as partial cable replacement, for life attainment or long term operation.

Particular attention has also to be paid to cable containment penetrations through the reactor building wall. These penetrations are one component in the overall cabling life management programme. While sealing performance is confirmed by the reactor building pressure test, the PLiM programme recommends additional condition assessment by supplementary tests specific to the penetrations themselves.

Procedures were developed to both examine these components in situ and to remove “aged” penetrations from the reactor building and replace, all during a planned outage. This removal will allow a number of potential ageing mechanisms, internal to the cable penetrations, to be assessed via direct tests on internal sub-components of these “aged” spare penetrations. For instance, at one Canadian HWR NPP, two “aged” penetrations were successfully removed and new ones installed. The overall duration of the activities was approximately one day. A programme of tests and analysis on these penetrations was defined and then implemented.