Support engineering

Maintenance, repair and operations (MRO) involves maintaining, repairing, and replacing if necessary devices, equipment, machinery, building infrastructure, and supporting utilities in industrial, business, governmental, and residential installations. Over time, this has come to often include both scheduled and preventive maintenance as cost-effective practices. Scheduled inspections have also come to fall under MRO purview.

More recently, 'predictive maintenance' is being employed, which uses sensor data to monitor a system, then continuously evaluates it against historical trends to predict failure before it occurs.

In aircraft maintenance, maintenance, repair and overhaul (MRO) services also include inspection, rebuilding, alteration and the supply of spare parts, accessories, raw materials, adhesives, sealants, coatings and consumables for aircraft manufacturing and MRO.

The marine transportation, offshore structures, industrial plant/equipment and commercial facilities market sectors depend on scheduled or preventive paint maintenance programmes to maintain and restore coatings applied to steel, and also concrete and masonry assets in environments subject to attack from erosion, corrosion and environmental pollution.

Over time, the terminology of MRO has begun to become standardized. The United States Department of Defense uses the following definitions:

The above also apply to the telecommunication, commercial real estate, and engineering in general.

Manufacturers and industrial-supply companies often refer to MRO as opposed to original equipment manufacturer (OEM). OEM includes any activity related to the direct manufacture of goods, where MRO refers to any maintenance, repair or overhaul activity to keep a manufacturing plant or facility running. Maintenance is strictly connected to the stage of ideation, in which the concept of maintainability must be included. In this scenario, maintainability is considered as the ability of an item, under stated conditions of use, to be retained in or restored to a state in which it can perform its required functions, using prescribed procedures and resources. Overhaul extends to the concept of improving performance over and above original design specification.

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Wikipedia