MTBF or MTTF? What We Should Really Be Measuring in Underground Mining

The debate remains open—and that makes me happy. Nothing is healthier for engineering than discussing with arguments. After my reflection on how MTBF is applied in underground mining, I received valuable comments from regulatory, operational, and strategic fronts. These conversations not only enrich the analysis but force us to refine what many take for granted, and to draw, once and for all, a clear line between continuous production processes and extractive processes: sequential, pulsating, and discontinuous. Some colleagues reminded me that the ISO/TR 12489:2016 standard presents a different view of MTBF, defining it as the sum of MTTF + MTTR. That is, what in other frameworks is known as TBF (Total Time Between Failures). Although initially designed for industrial safety systems, this approach makes perfect sense in underground mining, where repair time is not accessory: it is determinant for the continuity of the production cycle. Read the full article here to discover why true maintenance engineering doesn’t consist of applying universal formulas without context, but understanding what we measure, why we measure it, and how it impacts decisions on the ground.