Maintainability

It is described as the probability that a system might be restored to predetermined level of quality (or condition) in a specified period, when the maintenance is done with prescribed procedure and resources.

Better maintainability of an equipment means,

• The downtime of the system is low,
• Time to carry out preventive maintenance is low, and
• Time taken in fault-analysis, repair, replacement and subsequent operations are low.

The following terms are used in reference to maintainability

Mean Time between Maintenance (MTBF)

It indicates the frequency of maintenance.

Mean Time to Repair (MTTR)

It is mean time to require for repair of equipment. It does not include waiting time.