Management of ChangeMOC

Management of Change is the PSM element at 29 CFR 1910.119(l) and an ISO 45001 and ISO 9001 expectation under risk-based thinking. It captures the technical basis of a change, the procedures and documents it affects, the training the change requires, and the authorising approvals — all before the change is executed. The standard exists because a change made without analysis is one of the most common root causes in major-hazard incidents: a valve swapped for an incompatible one, a setpoint relaxed without re-rating the relief path, a new reagent introduced without updating the SDS.

An MOC that is treated as a formality — a checkbox a project manager signs the day before the change — is the one that produces the incident the program is later investigated for. A defensible MOC classifies the change (replacement-in-kind versus change), triggers a pre-startup safety review for the non-replacement cases, and feeds the mechanical-integrity program when the change touches equipment. The audit trail is the point: the record has to show what was changed, why, who approved it, and what was verified before the change went live. See PSSR, PSM, and HAZOP.