How much of your maintenance should be planned, what the ratio looks like across real plants, and why it correlates with OEE more strongly than almost any other single number.
Quick answer: A healthy manufacturing plant runs the clear majority of its maintenance hours as planned work; heavily reactive plants sit at the bottom of the OEE distribution. The ratio matters because reactive work costs three to five times more per fix, steals production time at the worst moments, and signals that failures, not priorities, are running the maintenance department.
The reactive vs planned ratio is the share of maintenance labor hours spent on unplanned, break-fix work versus work that was scheduled in advance: preventive tasks, planned corrective jobs, and inspections. It is a behavior metric disguised as a maintenance metric. A plant at 70 percent reactive is not unlucky; it is trapped in a loop where breakdowns consume the hours that prevention would have needed, which guarantees more breakdowns.
Vendor folklore quotes 80/20 planned-to-reactive as world class. Like most folklore numbers, it travels without its definition: whether changeover support, operator care and improvement work count as planned swings the ratio enormously. What we can say with measured data:
The direction is unambiguous even before the exact figures: when we split lines by OEE quartile, the top quartile plans most of its work and the bottom quartile firefights most of it, on the same kinds of equipment. Machines do not differ that much. Management systems do.
Better-maintained lines score higher, and better-run plants do both things well, so the ratio is partly a symptom. Operationally, the reading is identical either way: moving hours from reactive to planned is the intervention available to every plant this quarter, and it works through three mechanisms.
Planned work is cheaper per job because parts, tools and access are staged. Planned work happens in windows production agreed to, not in the middle of a run. And every planned hour reduces the failure population that generates the reactive hours.
First, measure it honestly. Most CMMS data flatters the ratio because reactive jobs done informally never become work orders. Automatic work-order creation from machine stops closes that hole. Second, protect one planned window per line per week and treat it as production time that belongs to maintenance. Third, rank the backlog by production impact in currency, so planned hours go where the OEE is. Fourth, attack repeat failures, because every eliminated repeat converts future reactive hours into free capacity.
Two audiences deserve a word of their own. For operators and technicians, the ratio is not an abstraction: a plant moving from reactive to planned work is a plant with fewer 2am callouts, fewer heroic weekends, and jobs done with the right parts staged instead of improvised under pressure.
Frame the program that way on the floor and the floor will feed it honest data. For group leadership, the ratio is one of the few maintenance numbers that compares cleanly across plants, provided the definition of planned is identical everywhere; under one definition it becomes a portfolio instrument, showing which sites need investment before their OEE says so.
How do we defend the planned window when production pushes back?
In currency, not principle. Price the window's cost in scheduled output against the reactive hours and failures it prevents, using your line's value per OEE point. Windows lose the argument when defended as policy and win it when defended as arithmetic.
What is a good reactive to planned maintenance ratio?
Directionally, plans should dominate: the strongest plants run a clear majority of hours as planned work. Treat published exact ratios skeptically unless the definition of planned is disclosed; the honest move is to baseline your own ratio and drive it up quarter by quarter.
How do I calculate the ratio?
Divide unplanned corrective labor hours by total maintenance labor hours over a period, using work-order data. The result is only as honest as your work-order discipline: informal fixes that bypass the system make the ratio look better than reality.
Does more preventive maintenance always help?
No. PM beyond the useful point wastes hours and can introduce failures. The goal is planned work aimed at real failure modes, which is why repeat-failure analysis and PM effectiveness review belong next to the ratio.
Why does reactive work cost more?
Unplanned jobs run without staged parts, interrupt production at uncontrolled moments, often occur at premium labor hours, and frequently fix the symptom under time pressure rather than the cause.
Fabrico measures the ratio automatically from machine-triggered work orders. See where your lines sit against the benchmark, or read how the ratio connects to OEE quartiles in our annual report.
Zakažite sastanak KSNUMKS-to-KSNUMKS sa našim stručnjacima ili se direktno upišite u naš besplatni plan.
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