Maintenance strategies focus on acting during which interval on the P-F Curve?

• A. Warning Period
• B. Repair Period
• C. Downtime
• D. Failure Window

Answer: (A)

The key idea is to act during the warning period. On the P-F Curve, P marks the start of potential failure and F marks actual failure. The interval between P and F is when degradation is detectable but the asset is still functioning. Intervening in this window lets you take preventive or corrective actions to halt progression to failure, reducing downtime and repair costs. Waiting until failure means you’re dealing with downtime and more extensive repairs, which is why the other options don’t fit as well. The term most aligned with proactive maintenance on this curve is the warning period.