MNT.6:4 - Solution

Begin with the requested decision and time horizon. Recover the relevant required function, current condition and failure account. Use already adequate evidence before asking for more. Separate the diagnosis supported now from the stronger causal account that may remain unresolved.

Form the alternatives that can answer this case. Include retaining the present arrangement, deferring with stated conditions, restricting operation, targeted inspection and stopping when they are plausible responses. Repair and replacement can have different support, downtime and recurrence consequences. A candidate without the means or authority for its actual performance can remain a recommendation, but it is not a feasible immediate act.

Compare the alternatives at the same required use. Explain what failure or condition each addresses, the consequence of delay, the expected intervention effect and its material uncertainty. Include disturbance, introduced defects, access, support, service loss and later restoration. Do not conceal an unacceptable condition by averaging it into a favourable cost score.

Test whether the remaining diagnosis uncertainty changes the choice. If all plausible mechanisms justify the same bounded response, give that response with its supported explanation. If one mechanism favours replacement and another would make it ineffective, seek the smallest worthwhile discrimination. State the result needed from a specialist rather than commissioning an unrestricted investigation.

Use MNT.5 and MNT.7 where support and operation can change feasibility. A part awaiting applicability evidence can block installation while leaving replacement at a suitable future outage as the best recommendation. If no feasible alternative preserves the required use, return the precise unmet condition to the appropriate operating or engineering decision.

State the chosen answer in ordinary terms: what to do or recommend, for which unit and configuration, under which conditions, why it is preferable and what would reopen it. Retain only uncertainty and conditions that change the recipient’s use. If the request is for advice and the answer is adequate, stop.

For performance of a selected intervention, carry the selected scope to MNT.8 and MNT.9. When an operative requirement is disputed, appraise its merits separately: the protected party, relevant harm, baseline and marginal protection, whole burden and displaced harm matter. Preserve present force while the authorized holder considers an amendment. A maintenance recommendation does not amend that requirement.