MTBF Interpretation in Underground Mining: Beyond Standard Definitions

The normative definition of MTBF that we see in point 1 has often been misinterpreted in underground mining. Part of the problem lies in its origin: these reliability indicators —MTBF, MTTF, and MTTR— were conceived in industries like aeronautics and electronics, where critical systems rarely stop. In those environments, failed components are immediately replaced by previously repaired units (line replaceable units), and repair occurs outside the main system. But in underground mining, the context is radically different. Here, when equipment fails, the operation stops, and repair time does matter, because it directly impacts the continuity of the extraction cycle. Unlike other sectors that apply componentization strategies and hot-swapping, in underground mining few equipment are designed for rapid field replacements. From my experience, in underground mining it’s more useful —for operational and planning purposes— to consider a metric that reflects total time between failures, including both repair time and subsequent operation time. Although this metric doesn’t strictly correspond to the MTBF defined by international standards, it better represents the operational reality of the field. Read the full article here to discover why true maintenance engineering doesn’t consist of copying formulas or blindly applying standards, but understanding their logic and adapting them with technical criteria to the terrain where we operate.