MTBCF is a measure of reliability for repairable items. The equation for calculating MTBCF is:

A critical incident is one that has a predetermined severity level. For example, within the Master List Library file, four severity items are defined for the Severity Military list: Catastrophic, Critical, Marginal, and Minor. For more information, see List Library Files. The filter for calculating MTBCF finds the number of closed, relevant, and chargeable incidents that have Catastrophic or Critical selected for Severity, Close Out.

Changing this calculation requires that an administrator specify criteria for the MTBCF filter in the Project Filter file. For more information, see Filters. To use different list items for Severity, Close Out, a Severity Military list with the appropriate items must be inserted in an enabled List Library file.