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Operations Management and Strategic Management · Designing of Operational Systems and Control

Maintenance Management and Operational Control Notes

Updated 10 October 2026 · Fact-checked

Maintenance management keeps plant and equipment in working order at the lowest total cost. The main types are breakdown (repair after failure), preventive (scheduled upkeep) and predictive (action based on measured condition). Operational control compares actual output, cost, quality and time with plans and corrects deviations. Choose the type by comparing costs and risk of failure.

Understand Maintenance Management and Operational Control

Maintenance management is the planning, organising and controlling of work that keeps machines, buildings and tools fit for use. A machine that stops unexpectedly delays orders, wastes labour, spoils work in progress and can harm safety. Maintenance exists to reduce these losses.

There are three main types. Breakdown maintenance (also called corrective or run-to-failure) means you repair or replace only after the equipment fails. It suits cheap, non-critical items with easy spares, such as a bulb in a store room. Preventive maintenance means inspecting, lubricating, adjusting and replacing parts on a fixed schedule, based on time or usage, before failure happens. It suits critical machines with predictable wear. Predictive maintenance means you measure the actual condition, for example vibration, temperature, oil quality or noise, and act only when readings show a problem is developing.

The difference between preventive and predictive is the trigger. Preventive is triggered by the calendar or running hours, so some parts may be changed while still good. Predictive is triggered by condition, so parts are used longer, but you need monitoring tools and trained staff. Some syllabus notes also mention routine maintenance (daily cleaning and lubrication) and corrective maintenance done to remove a known fault in a planned way. Use these terms as your notes define them.

Operational control is the wider activity of watching day-to-day operations and correcting them. You set standards for output, quality, time, cost and inventory. You measure actual results, compare, find the reason for the gap and act. Common tools are production control charts and Gantt charts, schedules and dispatching, inventory control, quality control and statistical process control, budgets and variance reports, and visual management. Maintenance records feed this control, because downtime directly lowers output.

The key idea for answers is balance. Too little maintenance raises breakdown losses. Too much raises maintenance cost. A good policy keeps the sum of maintenance cost and breakdown cost as low as possible, while meeting safety and quality needs.

Key rules to remember

Total maintenance-related cost
Total cost = Cost of maintenance work + Cost of breakdowns (lost contribution, idle labour, repairs, spoilage)
The best policy has the lowest total, not the lowest maintenance spend alone.
Cost of breakdown maintenance
Expected breakdown cost = Expected number of breakdowns × Cost per breakdown
Use the same time period for both sides when comparing policies.
Downtime (idle) loss
Downtime loss = Hours lost × Loss per hour
Loss per hour is usually contribution lost plus idle wages and fixed charges stated in the question.
Availability
Availability % = (Scheduled running time − Downtime) ÷ Scheduled running time × 100
A simple measure of how well maintenance supports operations.
Decision rule
Prefer preventive maintenance if total cost under preventive < total cost under breakdown
Mention non-cost factors such as safety and quality as well.

How to solve Maintenance Management and Operational Control questions

Use this method for both theory and numerical questions on maintenance and control.

  1. 1Read the question and mark the verb: define, differentiate, explain, compare, or compute.
  2. 2For theory, define the term in one line, then give features, advantages, limits and one suitable example.
  3. 3For differences, use two-column points on the same bases: trigger, timing, cost, suitability and risk.
  4. 4For numericals, list the cost of each policy for the same period: maintenance cost plus breakdown cost.
  5. 5Compute expected breakdown cost as number of breakdowns times cost per breakdown. Add downtime loss if given.
  6. 6Compare totals and choose the lower-cost policy.
  7. 7Add a line on non-cost factors such as safety, quality and equipment criticality.
  8. 8State a clear conclusion with the saving in rupees.

Quickest way: Three-line policy comparison

When to use it: Use when the question gives costs and breakdown counts for two or more maintenance policies.

  1. Write each policy as a column with maintenance cost, breakdown cost and total.
  2. Fill only numbers given, using the same period (month or year) in every column.
  3. Circle the lowest total, write the saving, and add one line on safety or criticality.

Common mistakes in Maintenance Management and Operational Control

  • Treating preventive and predictive maintenance as the same thing.

    Both act before failure, so they look alike.

    Fix: Remember the trigger: preventive is time or usage based; predictive is condition based and needs monitoring.

  • Choosing the policy with the lowest maintenance cost only.

    Students ignore breakdown losses.

    Fix: Always compute total cost including breakdown loss before deciding.

  • Mixing periods, such as monthly breakdown cost with yearly maintenance cost.

    Data is given in different units.

    Fix: Convert everything to one period before adding.

  • Saying breakdown maintenance is always bad.

    Overgeneralising from textbook warnings.

    Fix: State that it is economical for non-critical, low-cost, easily replaced items.

  • Writing operational control as only inspection.

    Students forget the corrective step.

    Fix: Write the cycle: set standards, measure, compare, find causes, take corrective action.

  • Giving no conclusion in numericals.

    Running out of time after calculation.

    Fix: Finish with one sentence naming the better policy and the saving.

Worked examples

Example 1

A machine has two options. Under breakdown maintenance, it fails 12 times a year; each breakdown costs ₹15,000 in repairs and lost output. Under preventive maintenance, annual servicing costs ₹60,000 and breakdowns fall to 3 a year at the same cost per breakdown. Which policy is cheaper?

Show the solution
  1. Breakdown policy: 12 × ₹15,000 = ₹1,80,000. No servicing cost, so total = ₹1,80,000.
  2. Preventive policy: breakdown cost = 3 × ₹15,000 = ₹45,000.
  3. Add servicing: ₹60,000 + ₹45,000 = ₹1,05,000.
  4. Saving = ₹1,80,000 − ₹1,05,000 = ₹75,000.

Answer: Preventive maintenance is cheaper by ₹75,000 a year (₹1,05,000 against ₹1,80,000).

Example 2

Differentiate between preventive and predictive maintenance. Then state when breakdown maintenance is acceptable.

Show the solution
  1. Trigger: preventive maintenance is done at fixed time or usage intervals; predictive is done when condition monitoring shows deterioration.
  2. Parts use: preventive may replace parts that still have life left; predictive uses parts closer to their full life.
  3. Cost and skill: preventive needs a schedule and records; predictive needs monitoring instruments and trained staff, so set-up cost is higher.
  4. Suitability: preventive suits equipment with predictable wear; predictive suits costly critical equipment where condition can be measured.
  5. Breakdown maintenance is acceptable for non-critical, low-cost items, where failure causes no safety risk, spares are easily available and standby exists.

Answer: Preventive maintenance is calendar or usage driven, while predictive is condition driven. Breakdown maintenance is acceptable only for non-critical, cheap, easily replaced items with no safety risk.

Exam tips

  • For 2-mark MCQs, link the key word to the type: scheduled means preventive, condition or monitoring means predictive, after failure means breakdown.
  • In descriptive answers, a short comparison table-style layout in points earns step marks; keep the same bases on both sides.
  • In numericals, show both policies' totals separately before comparing, so partial marks are safe.
  • Add one practical Indian example, such as a textile mill or auto component plant, to lift a theory answer.
  • Keep operational control answers in the cycle form: standard, measure, compare, correct.

Practice questions from Designing of Operational Systems and Control

Maintenance Management and Operational Control: frequently asked questions

What is the difference between preventive and breakdown maintenance?

Preventive maintenance is planned work done before failure to reduce its chance. Breakdown maintenance is done only after the equipment fails. Preventive costs more upfront but usually reduces costly stoppages on critical machines.

What is predictive maintenance in simple words?

It means you watch the machine's condition using readings such as vibration or temperature. You repair only when the readings show trouble is coming. This avoids both sudden failure and unnecessary replacement.

What are the main operational control techniques?

Common techniques include scheduling and Gantt charts, inventory control, quality control charts, budgets and variance reports, and production control through dispatching and follow-up. All of them compare actual results with plans and trigger corrective action.

Is breakdown maintenance ever the right choice?

Yes. For low-cost, non-critical items that are easy to replace and carry no safety risk, running to failure can be the cheapest policy.