Planned maintenance is a broad category that includes any maintenance activity that is organized and scheduled *before* a failure occurs.

It is the direct opposite of unplanned (corrective, emergency) maintenance.

Preventive maintenance is a *type* of planned maintenance.

However, not all planned maintenance is preventive in the traditional, time-based sense.

The key distinction lies in the trigger for the plan: - **Preventive Maintenance (Systematic):** The plan is triggered by a fixed schedule (time or mileage).

For example, 'Plan to change the tires every 50,000 miles.

' - **Condition-Based Maintenance:** This is also planned.

The plan is triggered when a sensor reading crosses a threshold.

For example, 'When the brake pad sensor indicates 3mm remaining, plan to schedule a replacement.

' - **Predictive Maintenance:** This is also planned.

The plan is triggered by an AI model's forecast.

For example, 'The AI predicts the water pump will fail in the next 1,000 miles.

Plan to schedule a replacement at the next service stop.

' Therefore, 'planned maintenance' is the umbrella term for all proactive work.

It encompasses identifying the need for a task (whether by schedule, condition, or prediction), ordering parts, assigning technicians, and scheduling the work to minimize disruption.

It is the hallmark of a well-organized and efficient maintenance operation.