RELIABILITYMETHOD

Reliability Engineering

MTBF

Mean time between failures (MTBF) is the average operating time between repairable asset failures.

Why it matters

Used with context, MTBF helps teams detect reliability trends and prioritize recurring failure modes.

How it works

MTBF works best as part of a closed-loop maintenance system: define a standard, execute it consistently, review performance, and improve the standard using evidence.

A practical step-by-step process

  1. 1Define the purpose, scope, and accountable owner.
  2. 2Establish a clear standard and required data.
  3. 3Pilot the process on a focused set of assets or work.
  4. 4Train the people who execute and review the work.
  5. 5Track performance at a consistent operating cadence.
  6. 6Correct gaps and improve the standard.

Common mistakes

  • Treating the metric as the goal instead of improving the work system.
  • Using inconsistent definitions across teams.
  • Collecting data without assigning ownership for action.
  • Changing too much before the baseline is understood.

KPIs to watch

MTBF by asset
Failure count
Operating hours

Frequently asked questions

Who should own MTBF?+

A named process owner should maintain the standard, while supervisors and frontline teams own consistent execution.

How often should performance be reviewed?+

Review operational exceptions weekly and overall trends monthly. Adjust the cadence to the risk and rate of change.

What is the best place to start?+

Start with one area, agree on definitions, establish a baseline, and improve the workflow before scaling.