Breakdown maintenance is service on failed equipment that has not received any scheduled maintenance. Breakdown maintenance is used only on equipment that is inexpensive and non-critical to facility operations. It is also the most expensive type of maintenance work.
Scheduled maintenance is work that is planned and scheduled. The goal is to minimize emergency work, and assure reliable and efficient operations that maintain required quality standards. Scheduled maintenance work includes periodic maintenance, corrective work and project work.
Predictive maintenance (PDM) is a growing area of preventive maintenance. PDM uses electronic monitoring equipment to warn of problems before they affect equipment performance. PDM requires a substantial investment in training and equipment and is most commonly used on expensive or critical equipment.