The delay-time concept and gamma process model have been widely applied in CBM settings. This paper reveals a close relationship between these two models. That is, given one of them, the other can be approximately determined. This nature is very useful in reliability modeling and maintenance decision analysis based on the delay time model or gamma process model because some analysis is easier for one of them than for the other. The method to make mutual conversions between these two models is developed and illustrated by three examples. The potential applications and possible extensions of the method are also discussed.
