Certified Maintenance & Reliability Professional (CMRP) Practice Exam

Maintainability of a system is primarily measured by the Mean Time to Repair (MTTR) because this metric specifically focuses on the average time required to repair a system after a failure occurs. MTTR is crucial in assessing how quickly a system can be returned to operational status, which directly reflects its maintainability. A lower MTTR indicates a system that can be repaired quickly, allowing for improved productivity and reduced downtime. In contrast, Overall Equipment Effectiveness (OEE) is a broader metric that evaluates the performance, availability, and quality of equipment, but it does not specifically isolate the maintainability aspect. Scheduled Maintenance Compliance focuses on adherence to proactive maintenance plans, which is valuable but does not directly quantify the efficiency of repairs. The Asset Availability Ratio measures the proportion of time that an asset is available for use, which is important but again does not assess the speed of repairs directly. Thus, MTTR serves as the most direct measure of a system’s maintainability.