ABSTRACT
Maintainer tasks generally require the use of skills, knowledge, or tools that are not normally available to the operators. Maintenance tasks include both disruptive interventions as well as nonintrusive monitoring activities. Recurring maintenance strategies are tasks that are carried out on a repeated basis, usually at a fixed frequency or task interval. Predictive Maintenance (PDM) is used to predict when a failure that has already begun will propagate to the point where it manifests as a loss of some functional capability. The restorative part of PDM comprises planned and scheduled maintenance. The repair of the failing condition must be done in time to avoid the loss of functionality or the consequences that will arise when functionality is lost. Recurring preventive, predictive, or detective tasks, whether they are performed by maintainers or operators, deal with the failures and their causes with the aim of reducing consequences to levels we can tolerate.
