Maintaining containment and function
Mechanical integrity brings together measures enabling equipment and installations to retain necessary safety conditions throughout service life. It includes design, selection, manufacture, installation, inspection, testing, maintenance and repair. It is not limited to whether a machine starts or a vessel has no visible leaks.
Related concept: Maintenance safety.
Components to identify
Scope depends on the process: vessels, pipes, valves, pumps, relief systems and other components whose loss of function could cause an accident. The inventory must distinguish critical components and design and operating conditions. Without that basis, connecting an inspection result with a safe decision is difficult.
Looking for deterioration that may occur
Corrosion, erosion, fatigue, embrittlement and seal degradation require different strategies. Inspection technique, location and frequency must address the expected mechanism and failure consequences. An identical schedule for all equipment may overlook highly stressed points or produce checks that cannot detect the relevant damage.
From inspection to a decision
The report must identify equipment, method, scope, result and limitations. Results are then compared with acceptance criteria to decide repair, replacement, operating restrictions or justified monitoring. Accumulating certificates without managing anomalies does not maintain integrity. Safety-critical defects must be resolved before continuing under unacceptable conditions.
Hypothetical example
A line changes product and starts operating at a higher temperature. Retaining the same inspection programme because it worked well previously ignores changed degradation mechanisms. Management of change must review materials, limits, seals, relief and controls, alongside updating documentation used by maintenance.
Scope and responsibility
Statutory inspections and the organisation’s programme complement each other; no generic checklist covers every failure mode. OSHA includes mechanical integrity in its PSM standard for processes within its scope. The concept may guide other workplaces, but it does not make US requirements universal obligations or replace local equipment regulations.
