What is Mean Time Between Failure? How to Calculate ...
The MTBF formula uses only unplanned maintenance and doesn't account for scheduled maintenance, like inspections, recalibrations, or preventive parts replacements. MTBF Calculation. To calculate MTBF, divide the total number of operational hours in a period by the number of failures that occurred in that period. MTBF is usually measured in hours. MTBF = # .