Reactive maintenance
What is reactive maintenance: run-to-failure explained
Reactive maintenance is repairing or replacing an asset after it has already failed, with no scheduled preventive work carried out beforehand, which means the failure itself decides when the work happens and what it costs. The US Department of Energy calls it the run-it-till-it-breaks mode, where no effort is made to keep equipment running as the designer intended. Breakdown maintenance and run-to-failure are the same thing under different names.
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Know what the job needs before the van rolls
Venta Capture, a product of VentaVid, lets the customer show you the fault first, so the engineer arrives with the right part or does not need to arrive at all.
It is not a strategy by default. It becomes one only when you have decided, asset by asset, that failure is the cheapest outcome.
What counts as reactive maintenance?
The word people trip over here is corrective. The two are not interchangeable:
- Reactive maintenance describes the strategy. Nothing was planned, so the failure sets the schedule.
- Corrective maintenance describes the work. Repairing a fault you found on a vibration route is corrective, and it is not reactive, because you chose when to do it.
Deferred maintenance is a third category worth separating out. Work that was planned, funded and then postponed is not run-to-failure. It is a backlog, and it usually converts into reactive work later at a worse price.
How common is reactive maintenance?
More common than most maintenance managers expect. The DOE Operations and Maintenance Best Practices Guide reports the average facility mix as more than 55 percent reactive, 31 percent preventive, 12 percent predictive and 2 percent other, and notes that reactive work is still the predominant mode in the United States. Continually top-performing facilities sit at under 10 percent reactive, with 25 to 35 percent preventive and 45 to 55 percent predictive.
Estimates of the right level vary, and they are measured differently. NIST's report on the costs and benefits of advanced maintenance in manufacturing (Douglas S. Thomas, 2018) cites an ideal level of reactive work of 30 to 40 percent of total maintenance time, against a Swedish survey putting practice at about 50 percent. Before comparing your own figure with either benchmark, check whether it counts share of labour hours, share of work orders or share of maintenance spend, because those three answers are rarely close.
Why reactive maintenance costs more than it appears to
Reactive maintenance genuinely does have low up-front cost and it needs fewer planners. That is the case for it, and it is also how the real cost hides. The DOE guide sets out where the money actually goes:
- Unplanned downtime. The failure picks the moment, and it is rarely a convenient one.
- Overtime labour. Failures cluster outside normal hours, and critical assets have to come back regardless.
- Secondary damage. A failed component takes another one with it, a cost that would not have existed under a more proactive approach.
- Larger spares inventory. If you expect to run to failure, you have to hold parts for failures you cannot predict.
- Shortened asset life. Running degraded equipment to the point of failure brings the replacement date forward.
On the cost-per-horsepower comparison reproduced in the DOE guide, reactive maintenance runs at $18 per horsepower per year against $13 for preventive, $9 for predictive and $6 for reliability centred maintenance. The dollars are dated. The ranking has held up.
Reactive maintenance explained: a worked example
A conveyor gearbox bearing fails at 11pm on a Friday. The repair takes six hours at overtime rates, an expedited coupling on next-day freight, and a shaft that was scored during the failure and now has to be replaced too. Change the same bearing on condition, during a planned shutdown, and it is around 90 minutes at day rate with a stocked part. The bearing costs the same in both stories. Everything around it does not.
When reactive maintenance is the right choice
Reliability centred maintenance says so explicitly: assets that are inexpensive and unimportant to facility reliability are often best left to a reactive approach. That is why top performers report under 10 percent reactive rather than zero.
Run to failure when the asset is cheap to replace, easy to get at and quick to swap, when failure has no safety, environmental or compliance consequence, when a spare is on the shelf or redundancy covers the loss, and when there is no gradual failure mode worth monitoring anyway. Light fittings and small circulation pumps usually qualify. A critical process compressor never does.
The distinction to hold onto is between chosen reactive work and unchosen reactive work. The first is a documented decision with a spare in stock. The second is what happens when nobody decided. Both show up in the same column of the report, and the two things they cost you are not remotely alike. Tracking first-time fix rate and the avoidable truck roll alongside the mix is what tells you which one you are actually running, and better pre-visit assessment is usually the first thing that shortens the unplanned half.
