MNT.Preface:3 - What the principal objects mean in practice

A maintained System is the equipment or other System whose contribution is at issue. A part is an actual constituent; a part number can describe many such individuals. A configuration is the relevant actual arrangement and values over an interval; a configuration description carries claims about it.

An observation says what was measured or inspected. A diagnosis explains the condition to the degree supported. A prognosis concerns future condition under stated assumptions. The maintenance choice uses these accounts but also considers feasible response and consequence.

A policy is the reusable selection of task and applicability conditions. A particular intervention decision selects a response now. A Method is a reusable way of obtaining a result; this framework’s pattern prose explains those ways. A plan describes intended work, while the performed work and its effects require evidence of what occurred.

These distinctions matter where they change action. Ordinary equipment and maintenance language is enough elsewhere; a routine repair need not acquire an ontology form. FPF supplies the general recognition, evidence, comparison, permission and assurance Methods. MNT adds the failure, task, support, operating and restoration reasoning that those general contributions do not decide by themselves.