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consistent with the existing capabilities of the facility or that needed upgrades to the facility's
measurement capabilities are feasible.
A final list of periodic material condition measurements should be developed based on the results of
facility remaining lifetime determination, the previous baseline measurements, and the capabilities of
the facility. In addition, consideration should be given to establishing measurement methods that can
reasonably be expected to provide consistency and repeatability among different personnel across a
period of several years.
Various monitoring methods, including continuous monitoring or scheduled inspections, provide
periodic material condition measurements that determine current performance or condition. Observed
values are then compared with minimum acceptance criteria and with results of previous observations
on the same components. Criteria can be established so that corrective action is initiated when
monitored parameters deteriorate to a specified level or vary in a specified manner.
Equipment monitoring does not always uncover aging degradation. For example, electronic
components tend to fail catastrophically at random times, rather than degrading slowly over time in
service. For this type of equipment, trending component failure rates may be the only appropriate
method of monitoring aging. If sufficient statistical data are available, it is possible to schedule
surveillance, preventive maintenance, or replacement more effectively. For example, if the failure
pattern of a component shows that the probability of failure increases significantly after a certain time,
replacement of equipment may be scheduled. This type of trending entails a systematic collection and
analysis of operational data. The recording of equipment deficiencies in a specified, systematic manner
makes it possible to determine the severity of failures, failure modes, and root causes of failures, and to
monitor trends of failures and their causes.
4.4.2 APPLICATION OF LIFE EXTENSION TECHNIQUES
If the need for life extension techniques was apparent at the time of the detailed phase of the MCA
program, the feasibility study should have included recommendations for life extension techniques, at
least the preliminary development of those techniques, and estimates of the costs involved. That study
should be used as the starting point for the ongoing phase of the MCA program. If life extension
techniques have not been developed, or a new need for them should arise, they would be developed
during the ongoing MCA phase.
During the ongoing phase, the life extension techniques are finalized and established as new
requirements. Because these techniques often involve new design requirements, such as operating
conditions or operational limitations for equipment, design authority is the appropriate organizational
unit to review proposed life extension techniques. The operations organization staff also need to be
involved in many situations to develop appropriate practical operating scenarios. In addition, the design
authority should coordinate with the maintenance department to determine appropriate actions to be
taken with regard to MCA for selected non-life-limiting components.
4.5 SPECIFIC APPLICATION OF GRADED APPROACH: MCA ADJUNCT
PROGRAM
SSC grades are not significant to the main thrust of the MCA adjunct program. The MCA program is
focused on life-limiting components, which can include components of any grade. This approach is
necessary to arrive at a viable determination of the facility remaining lifetime. Other graded-approach
considerations that are generally applicable to implementation of the MCA program are remaining/
desired lifetime, operational status, and facility life-cycle phase. Remaining/desired lifetime and
II-101
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