Quick Answer
To manage planned vs unplanned maintenance, mining and field service contractors should:
- Aim for a 80% planned / 20% unplanned work ratio
- Define service intervals once per asset type and inherit them
- Run digital prestarts so defects are caught, not lost
- Triage every defect: run, repair-at-next-service, or stop-the-job
- Root-cause every unplanned failure and feed it back into the plan
- Track schedule compliance, MTBF and backlog age monthly
Unplanned maintenance typically costs 3–9x the equivalent planned job once lost production, freight and overtime are counted. Shifting the ratio is the highest-leverage move in a contractor's maintenance program.
Why the planned/unplanned split matters
Every hour of unplanned downtime on a mining or field service job hits three lines at once: lost production, expedited parts and overtime labour. On big iron the number climbs fast — a haul truck parked for a day can burn six figures before the wheels turn again.
Planned maintenance flips that maths. Work is quoted, parts are on the shelf, the window is coordinated with the client, and the tech isn't diagnosing under a torchlight at 2am. Getting the split right isn't a workshop metric — it's a margin lever.
Planned vs unplanned at a glance
Planned maintenance
- Scheduled by hours, kilometres or calendar
- Parts and labour organised in advance
- Done during a planned window — no production hit
- Predictable cost; can be quoted and job-costed
- Extends asset life and warranty coverage
Unplanned maintenance
- Triggered by a defect, fault or breakdown
- Parts often expedited at 2–5x normal cost
- Stops production — every hour has a dollar cost
- Overtime, callouts and travel drive labour up
- Higher risk of secondary damage and safety incidents
The 80/20 target and what it means
Most well-run mining maintenance programs sit around 80% planned and 20% unplanned by labour hours. It's not a magic number — it's what the industry consistently shows produces the lowest total cost of ownership.
< 70% planned
Firefighting
You're reacting more than planning. Costs and safety risk climb.
70–90% planned
Healthy
Predictable workload, room for continuous improvement.
> 90% planned
Over-serviced
Likely doing work the asset doesn't need — burning parts and hours.
A 6-step framework to shift the ratio
- 1
Define the plan
Set service intervals for every asset type once — hours, km or calendar, whichever comes first. New assets inherit the plan automatically.
- 2
Run digital prestarts
Every start of shift, the operator confirms the machine on a phone or tablet. Defects raise a work order in the same tap — nothing gets forgotten.
- 3
Triage every defect
Sort defects into 'run', 'repair at next service' or 'stop the job'. This is where planned wins — most unplanned events are avoidable if triage is disciplined.
- 4
Batch the work
Group planned services, deferred defects and inspections into the same shutdown or workshop visit. One touch of the asset instead of three.
- 5
Root-cause the unplanned
Every unplanned event gets a 5-Whys. The output feeds back into the planned schedule so the same failure doesn't happen twice.
- 6
Report the ratio
Track planned vs unplanned as a monthly KPI. Trend matters more than the point-in-time number.
The KPIs that actually move the needle
| KPI | Target | Why it matters |
|---|---|---|
| Planned vs unplanned ratio | 80 / 20 | Balance of proactive vs reactive work |
| Schedule compliance | > 90% | Are planned services actually done on time? |
| Mean time between failures (MTBF) | Trending up | Assets running longer between failures |
| Mean time to repair (MTTR) | Trending down | Faster response and turnaround |
| % of defects caught at prestart | > 60% | Front-line finding beats breakdown finding |
| Backlog age (avg days open) | < 14 days | Deferred work isn't ignored work |
Pick three to start — planned/unplanned ratio, schedule compliance and backlog age. Layer the rest in as the program matures.
Warning signs you're too far into unplanned
Red flags from the workshop floor
- The same asset breaks down for the same reason twice in a quarter
- Parts are regularly air-freighted or paid on 'urgent' surcharges
- Techs are on overtime chasing breakdowns instead of hitting scheduled services
- Prestarts are ticked without reading — defects only surface at breakdown
- Nobody can tell you the planned vs unplanned ratio for last month
- Warranty claims get knocked back because service history is patchy
How SprintSuite balances the two
SprintSuite ties assets, prestarts, work orders and scheduling into one flow — so planned work stays on the calendar and unplanned events feed straight back into it.
Asset management
Service intervals by hours, km or calendar — assets inherit the plan and alert when they're due.
Workshop management
Digital work orders for both planned and unplanned jobs, with parts, labour and photos in one record.
Health & safety
Prestarts and inspections that raise work orders the moment a defect is logged.
Frequently asked questions
Keep reading
Shift your workshop from reactive to planned
SprintSuite gives contractors one place for assets, prestarts, work orders and scheduling — so the 80/20 ratio isn't a spreadsheet exercise, it's how the day runs.
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