Achieved Availability
Achieved availability is the proportion of time an asset is available when corrective and preventive maintenance are included but logistics and administrative delays are generally excluded.
What this term means in maintenance
Achieved availability is the proportion of time an asset is available when corrective and preventive maintenance are included but logistics and administrative delays are generally excluded.
What achieved availability represents
It reflects the effect of:
- Failures
- Corrective maintenance
- Preventive maintenance
- Active maintenance time
Simplified concept
Achieved availability = Mean time between maintenance ÷ (Mean time between maintenance + Mean active maintenance time)
Why it differs from inherent availability
Inherent availability excludes preventive maintenance. Achieved availability includes it.
Why it differs from operational availability
Operational availability also reflects actual logistics, waiting, and support delays.
Practical use
The measure helps evaluate the combined effect of maintenance strategy and maintainability.
Common mistake
Using achieved availability without defining the included maintenance and delay categories makes comparisons unreliable.
How this term differs
Achieved Availability is availability including active corrective and preventive maintenance but normally excluding logistics delay. It is related to OEE Availability, Operational Availability, and Inherent Availability, but these terms describe different records, measures, roles, strategies, or decisions and should not be used interchangeably.
Related concepts
Related maintenance terms
Keep exploring connected CMMS, reliability, and maintenance planning terms.
Preventive Maintenance
Preventive maintenance is planned work performed at defined time, usage, or meter intervals to reduce the likelihood of equipment failure or deterioration.
Operational Availability
Operational availability is the proportion of total required time that an asset is ready for use under actual operating and support conditions.
Inherent Availability
Inherent availability is the theoretical availability of a repairable asset based on failure frequency and active corrective repair time, excluding planned maintenance and support delays.
Glossary FAQs
- What is achieved availability?
Availability including corrective and preventive active maintenance.
- How is it different from inherent availability?
It includes preventive maintenance.
- How is it different from operational availability?
It generally excludes logistics and administrative delays.