MTBF

The abbreviation for Mean Time Between Failures. The most widely used metrics for tracking the reliability of process machinery throughout the industry. To calculate, take the number of failures in a given time period and the total number of machines in the population.

where M is the total machine count; T is the reporting time; and R is the total number of repairs during the reporting period. (Example: There are 200 pumps in a population that experiences 20 failures in a three-month period. This group of pumps has a MTBR of 200 × 3/20, or 30 months between repairs.)