I would like to open a discussion regarding the definition and measurement of MTTR (Mean Time To Repair).
According to the SMRP Best Practices, page 83, MTTR starts when the technician arrives at the equipment and ends when the asset is restored to an operable condition. Based on this definition, technician travel time is not included in MTTR.
From a technical perspective, this approach makes sense when MTTR is used to assess maintainability, understood as an intrinsic characteristic of the asset. Including delays related to logistics, distance, access, or organizational constraints-factors external to the equipment-could distort the true evaluation of maintainability.
In practice, however, many organizations include travel time within MTTR to better reflect perceived downtime, especially in large plants, mining operations, or geographically dispersed assets.
I'd be interested to hear the group's perspective:
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Do you exclude technician travel time when MTTR is used specifically for maintainability analysis?
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Do you track travel or response time as a separate metric, keeping MTTR aligned with SMRP guidance?
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How do you handle this definition when MTTR is used for benchmarking or contractual KPIs?
Looking forward to your insights and practical experiences.