The MTBF distribution of a machine that has passed the phase of early failures exhibits a normal distribution. The smaller the standard deviation of this distribution
A) the more expensive is preventive maintenance
B) the more likely this machine is a candidate for preventive maintenance
C) the shorter is the time interval between breakdowns
D) the more likely this machine will break down
E) the more likely this machine will be maintained by a breakdown maintenance policy

Question

Quizplus · Accepted Answer

A smaller standard deviation means that the machine is less likely to deviate from its average MTBF, making it more predictable and therefore easier to schedule preventive maintenance. Therefore, it is more likely to be a candidate for preventive maintenance.

The MTBF Distribution of a Machine That Has Passed the Phase