Why Preventive Maintenance Matters
An unplanned breakdown can leave operators and other equipment waiting as well as create a repair bill. Start with the actual interruption: which machine stopped, what work couldn't continue, how long it lasted and what replacement capacity was available. Record direct repair costs separately from estimated production losses so the same delay isn't counted twice.
Planned maintenance gives your team a chance to arrange parts, people and a service window before a task becomes overdue. It doesn't remove every failure. Keep fault reporting and safe isolation procedures alongside the schedule, and review recurring defects rather than assuming a calendar reminder has solved them.
Build the financial case from your own records. Compare similar machines and operating conditions over a stated period, including planned labour, parts, breakdown repairs, hire costs and lost productive time. Label estimates and missing records. This guide doesn't prescribe a percentage saving or a universal daily downtime cost.
Safety-critical tasks need their own priority and escalation path. A cost-saving target shouldn't decide whether equipment with an unresolved safety defect returns to work. Make the responsible person and return-to-service decision visible in the maintenance record.
Time-Based vs Meter-Based Scheduling
The two fundamental approaches to scheduling preventive maintenance are time-based (calendar intervals) and meter-based (usage triggers). Most heavy equipment programs use both, applying whichever condition is reached first.
Time-based scheduling uses a calendar due date. It's useful when a task has an age-based requirement, but the interval must come from the applicable equipment schedule. Keep the requirement, last completion date and next due date together. The calendar examples in this guide are illustrative and aren't instructions for a particular machine.
Calendar time alone doesn't describe how much a machine has worked. Two otherwise similar machines can accumulate very different operating hours in the same month. Where the approved schedule also specifies usage, track both limits and identify which one is approaching first.
Meter-based scheduling uses operating hours, kilometres or cycles. For example, a hypothetical task due every 250 operating hours would next fall due at 1,250 hours after completion at 1,000, if its approved rule resets from completion. That arithmetic isn't an oil-change or inspection recommendation. Meter-based maintenance depends on the correct task rule and a trustworthy reading.
Check where each meter reading comes from and when it was last refreshed. Before using a telematics integration, confirm the supported provider, machine identifier and meter mapping for your setup. A stale or missing reading needs an exception process, not an assumption that the machine hasn't worked. Keep a manual reading option when the connection is unavailable.
The combined approach. When the equipment schedule specifies both calendar and usage limits, keep both visible and act on the first due condition. Record which task was completed and how its next due point is calculated. A calendar task and a meter task may require different reset rules; test the setup with a known completion before applying it across a fleet.
Service Trigger Decision Table
Use this table when setting up or checking a schedule. Keep the exact machine's approved task and manual reference beside each rule. It doesn't replace the manufacturer's schedule or your site's procedures.
| Trigger | Record | Decision |
|---|---|---|
| Calendar | Task, last completion, next due date and source requirement. | Plan against the approved date. Low use doesn't cancel a calendar requirement. |
| Hours, kilometres or cycles | Meter type, reading, reading time and next due point. | Compare a current reading with the correct task threshold. |
| Calendar and usage | Both limits, plus the rule for resetting each after completion. | Where specified, act on whichever comes first. Closing one task mustn't silently reset another. |
| Missing or stale reading | Last trusted reading, feed issue and person checking it. | Obtain a current reading and assess due work. Don't treat missing data as zero use. |
| Defect or condition finding | Asset, finding, severity and required assessment. | Follow the defect and isolation procedure. A future service booking isn't clearance to keep operating. |
For example, suppose an approved task is due at 1,250 hours or on 30 September, whichever comes first. A current reading of 1,260 hours means the usage limit has passed even if the calendar date hasn't. If the last reading is 1,180 hours but is a week old, the due state needs checking. These numbers illustrate the decision, not a service interval.
Setting Up Maintenance Intervals
Use the service schedule for the exact model, serial range and configuration. Store its revision and the task reference with the asset so someone can check where each requirement came from. If information is missing or doesn't fit the equipment, escalate it before choosing a replacement interval.
Use the correct manufacturer schedule. Transfer the task, interval, conditions and required checks into your maintenance platform. Keep the source document linked and have the responsible person check the setup. Don't copy an interval from a similar machine merely because its description looks familiar.
Check severe-service requirements. Dust, heat, salt and duty cycle may change the applicable requirements. Follow the manufacturer's instructions for those conditions and consult it about gaps. Don't apply a blanket percentage reduction to every service interval. Safe Work Australia's model plant code, section 3.6, addresses manufacturer specifications and competent-person recommendations where specifications are absent.
Group approved tasks carefully. Service groups can make work easier to plan, but each task should retain its own requirement. Avoid a generic service-level template that silently replaces the machine's actual tasks or intervals. Identify which inspections, consumables and specialist checks belong in each group, and retain exceptions for different configurations.
Build a master schedule. Once intervals are set for each asset, scheduling tools let you view all upcoming maintenance across your fleet in a calendar or timeline view. This lets you batch services (do three machines in the same week at the workshop rather than three separate call-outs), plan parts ordering in advance and coordinate with operators on downtime windows.
Work Order Workflows
A maintenance schedule tells you when to service. Work orders tell you what to do, who does it and whether it was done correctly.
Creating work orders. A useful work order identifies the asset, task, due point, assigned person, required parts and safety instructions. Where automatic creation is configured, test a known due condition and the resulting work order. Keep an overdue review so a failed reading, configuration or notification doesn't leave work unnoticed.
Assigning and prioritising. Use task criticality, the approved due limit and equipment availability to plan the work. A booking preference doesn't extend a safety-critical interval. Assign a person with the required competence, make deferrals visible and record who can approve them under your procedures.
Completing and closing. Record the work actually performed, parts, labour, readings, evidence and any outstanding defect. Check the configured next-due rule when closing the job. Completion, inspection sign-off and permission to return equipment to service are separate decisions when your procedure requires them.
Unplanned work orders. Keep faults and breakdowns visible alongside scheduled work. Compare planned and unplanned work using the same measure, such as labour hours or cost, rather than mixing job counts with hours. Break the result down by failure type and criticality; there isn't a single planned-work percentage that establishes a healthy programme.
Defect-to-Job Handover
A useful handover lets the next person see what's wrong, what needs doing and who's responsible. Copy these headings into your existing defect and work-order records, then add your equipment-specific requirements.
| Stage | Keep together | Check before moving on |
|---|---|---|
| Report | Asset ID, location, finding, time, reporter, reading and supporting photos. | The finding identifies the right machine and reaches an assigned person. |
| Assess | Severity, competent assessor, operating restriction and isolation status where required. | The responsible person records the immediate action and escalation. |
| Plan the job | Linked defect, work-order ID, approved task, technician, parts and due point. | The job has an owner. A booking or notification alone doesn't close the defect. |
| Complete and verify | Work performed, readings, parts, evidence, outstanding actions and required sign-off. | Record the return-to-service decision separately where the procedure requires it. |
| Review | Next due point, recurring-fault check and any remaining action owner. | A closed job hasn't hidden an unresolved defect or incorrectly reset a service trigger. |
This is a practical record structure, not a universal legal checklist. Check the Safe Work Australia model plant code and your local requirements. Sections 3.5, 3.6 and 6 cover maintenance, inspection and records. Source reviewed 15 September 2026.
Parts and Inventory Management
A maintenance schedule without parts on hand is just a list of good intentions. Parts availability directly determines whether scheduled maintenance happens on time or gets deferred, and deferred maintenance is the first step toward a breakdown.
Identify critical spares. Link the required part specification and quantity to the approved task. Choose stocking levels using criticality, supplier lead time, demand and shelf life. Some items justify a local spare; others need a confirmed supply arrangement. Review substitutions with the responsible technician rather than assuming interchangeable descriptions mean interchangeable parts.
Set reorder points. Use your inventory records to compare available stock with upcoming work. Allow for actual supplier lead times and the buffer your operation needs. Test any configured low-stock alert and assign someone to action it; a notification isn't a placed order.
Link parts to work orders. Record the parts used against the job and reconcile the corresponding stock movement. Check that your configured workflow handles issues, returns and substitutions correctly. Use physical counts to investigate discrepancies rather than treating a software balance as proof that a part is on the shelf.
Track costs. Keep parts, labour and external repair charges against the relevant asset and period. Compare those costs with operating hours and the work delivered. A repair-or-replace decision also needs condition, reliability, replacement cost and operating requirements; maintenance cost alone doesn't settle it.
Compliance Documentation
Check the rules that apply to the location, equipment and work. Keep statutory requirements separate from your company's preferred reporting fields.
Check the applicable requirements. Safe Work Australia's model plant code covers competent-person maintenance and inspection in sections 3.5 and 3.6. Section 6 addresses records, including specific categories of plant. The code's legal effect depends on the jurisdiction; check the local regulator. Source reviewed 8 September 2026.
Keep a usable record. As an operational checklist, record the asset, task, completion date, meter reading, work performed, parts, technician, evidence and outstanding actions. Add any fields required by the applicable procedure or law. Link supporting records to the asset through your compliance workflow, and check who can retrieve them.
Connect pre-start findings to action. Use pre-start inspections to record the required checks and defects. Confirm that the chosen follow-up workflow assigns an owner and escalation. A submitted form isn't proof that a defect was repaired or equipment was cleared for use.
Test retrieval. Choose a completed job and check that another authorised person can find its source requirement, work record and unresolved actions. Repeat the check for older equipment and changed ownership or location. Measure retrieval time if it matters to your operation; don't assume a digital record guarantees a complete audit response.
Measuring Maintenance Effectiveness
Setting up maintenance schedules is step one. Measuring whether they are working is what drives continuous improvement.
Planned maintenance compliance (PMC). Divide scheduled tasks completed on time by the tasks due in the same period, using one documented rule for rescheduling and deferrals. Report safety-critical overdue work separately. Set a target for your operation and investigate misses; a universal percentage doesn't prove safety or predict every other outcome.
Mean time between failures (MTBF). For repairable equipment, divide observed operating time by qualifying failures in the same period. Define what counts as a failure and compare similar assets and duty cycles. With few or no failures, report the exposure and count rather than inventing a stable rate. An improvement can have several causes, including a change in workload.
Mean time to repair (MTTR). Divide the included repair time by completed qualifying repairs. State whether waiting for parts or a technician is included; changing that boundary can change the result without making repairs faster. Report unresolved repairs separately so long-running jobs don't disappear from view.
Maintenance cost per operating hour. Divide the included maintenance expenditure by operating hours for the same asset group and period. Keep the cost categories consistent. Show missing hour readings and one-off repairs, and avoid dividing by zero when equipment hasn't operated.
Equipment availability rate. Divide time available for the required work by scheduled operating time, using a stated treatment of planned maintenance and standby. Keep the denominator stable and show critical-asset exceptions. A change in the production schedule can alter availability even when reliability hasn't changed.
Build a regular maintenance report using those definitions. Review overdue critical work first, then recurring failures, parts delays and data gaps. Record the action, owner and next review date so the report leads to a checkable improvement. Treat before-and-after movement as an observation until comparable equipment and operating conditions support the conclusion.
