Book a demo
Login
Management of Change (MOC) is the formal process industry discipline for evaluating, approving, and documenting any change to a facility, process, or procedure before it is implemented — covering physical modifications, changes to operating parameters, and changes to procedures — to ensure the change doesn't introduce unrecognized safety, environmental, or operational risk. It is a core requirement of process safety management in oil, gas & LNG, chemical & process, utilities, pharmaceutical, and other capital-intensive industries.
MOC is a physical and procedural change discipline; it should not be confused with change control for master data, which governs how the data records describing assets are updated. The two are related — a facility change managed through MOC almost always requires an update to the underlying tag, drawing, and equipment data — but they answer different questions and are typically owned by different teams.
An MOC is typically required for any permanent or temporary change to equipment, process conditions, procedures, organization, or safety systems that falls outside the facility's approved design basis — for example replacing equipment with a non-identical substitute, changing an operating setpoint, modifying a safety interlock, or altering a documented procedure. Like-for-like replacements that stay within the original design basis generally do not require a full MOC review.
A typical MOC process includes: identifying and describing the proposed change; a risk assessment covering safety, environmental, and operational impact; technical review and approval by relevant engineering disciplines; updating affected documentation, drawings, and procedures; training or communicating the change to affected personnel; and a final review confirming the change was implemented as approved before it is closed out.
An MOC that is approved but never reflected in the affected P&IDs, tag data, or procedures creates exactly the kind of divergence between documentation and physical reality that as-built documentation is meant to prevent. Every approved MOC should trigger a corresponding update to the Master Tag Register and any affected drawings — closing the loop between the change decision and the documented state of the facility.
Management of Change asks: is this physical or procedural change to the facility safe, and has it been properly reviewed and approved? Change control for master data asks: has the resulting change to tag, equipment, or attribute data been made correctly, by an authorized person, with proper approval and audit trail? A facility change typically flows through both processes — MOC approves the physical change, master data change control governs how that change gets reflected in the authoritative asset records.
Sharecat ensures that once an MOC is approved and implemented, the resulting updates to tags, drawings, and equipment attributes are captured through a governed change control process — keeping the Master Tag Register and associated documentation synchronized with what MOC approved, rather than leaving a gap between the safety review and the documented state of the asset.
What is Management of Change in process safety?
It is the formal review and approval process required before implementing any change to a facility, process, or procedure that falls outside its approved design basis, intended to catch safety, environmental, or operational risks before the change is made.
Is Management of Change the same as change control for data?
No. MOC governs changes to the physical facility, process, or procedures. Change control for master data governs how the resulting changes to asset records and attributes are made and approved. See the comparison above.
Does every equipment replacement require an MOC?
No. A true like-for-like replacement within the existing design basis typically does not require a full MOC review, while any non-identical substitution, or a change to process conditions or procedures, generally does.
ISO
27001
Certified
