Planned vs Reactive Maintenance in Mining: Cost & Strategy

Because the wrench-time is nearly the same, but everything stacked around an emergency is extra. When a component fails unexpectedly you typically pay overtime or after-hours labour rates, expedite parts by air-freight instead of ordering ahead at list price, burn technician hours on diagnosis that a planned job already has done, mobilise a crew and tooling to a remote location at short notice, and often repair collateral damage because a component run to catastrophic failure takes its neighbours with it. On top of all that sits the lost production, because the breakdown happens when you needed the machine, not when you could spare it. Industry estimates for the emergency premium vary widely — commonly cited as roughly three to nine times the planned cost of the same job — and the reason it's a range rather than a fixed figure is that it depends on how many of those cost layers stack up on a given failure. Comparing a planned job's cost to an emergency invoice only fairly when both use the same total-cost definition.

As a general benchmark, average maintenance operations sit somewhere around 50% planned work, strong reliability programs run in the 80–90% range, and a fleet operating under about 30% is essentially firefighting full-time. An 80/20 split — 80% planned, 20% reactive — is a widely used target for a mature program. That said, aiming for 100% is neither realistic nor healthy: some genuine emergencies will always occur, and a suspiciously high planned percentage can actually be a red flag that failures are being miscategorised or suppressed rather than prevented. It's also worth calibrating the target to your risk profile — a critical constraint asset justifies pushing harder toward planned work than a redundant one. The number matters less as an absolute score than as a trend: a fleet moving from 40% toward 70% over a year is winning, regardless of whether it ever hits a textbook benchmark. Track it monthly and watch the direction of travel.

They measure different stages and you need both, because one can look fine while the other quietly fails. Planned work percentage measures preparation — what share of your maintenance work was planned in advance versus arriving as unplanned break-in or emergency work. Schedule compliance measures execution — of the work you planned and froze into the weekly schedule, how much actually got done as scheduled. A team can plan a lot of work (good planned %) but still execute poorly if emergencies keep displacing the frozen schedule (low compliance), which means the plan is effectively fiction. Conversely, high compliance on a tiny amount of planned work isn't impressive either. Read together with backlog health — the identified-but-not-yet-done work and how fast it's aging — the three give an honest picture: planned % shows how much you prepared, compliance shows whether you executed, and backlog aging warns what's about to turn reactive. No single one of them proves a fleet is reliable on its own.

Backlog is the pipeline through which planned work quietly becomes reactive work. Every deferred job — a hose flagged on inspection, a worn pin you'll address next window — sits in backlog until it's actioned. Managed well, that's healthy: a known queue of identified work waiting for the right maintenance window, planned and resourced deliberately. The danger is neglect. When backlog isn't actively worked down, jobs age, and aged backlog is simply breakdowns you've scheduled for yourself without setting a date — the flagged hose eventually bursts on shift and becomes an emergency. A backlog that grows month over month, or one where the oldest items keep getting older, is one of the earliest and clearest signals that planning or resourcing is falling behind demand, usually well before it shows up as a spike in emergency work. That's why controlling backlog — converting identified work into planned jobs before it fails — is a core part of moving a fleet from reactive toward planned maintenance rather than a separate housekeeping task.

Gradually, and by changing the workflow rather than exhorting the crew — reactive teams are already working flat out, so "try harder" doesn't work. The realistic sequence starts with protecting the planned schedule: only genuine emergencies are allowed to break the frozen weekly plan, while everything else enters the backlog to be planned properly, because without that discipline nothing else holds. Next, get preventive maintenance firing on real meter hours so services come due when a machine has actually done the work, generating a steady base of planned jobs. Then attack the biggest lever — convert defects found on daily and weekly inspections straight into scheduled corrective work orders, catching would-be breakdowns while they're still cheap. Make sure parts are lined up against inventory before a job is scheduled, so planned work doesn't stall into a last-minute scramble. Finally, measure planned percentage and schedule compliance monthly and track which failures keep recurring, since each repeat is a target for a reliability fix. HVI supports this whole chain with meter-based PM, defect-to-work-order automation, parts and inventory checks, and analytics. You can book a demo to see the workflow end to end.