Management of Change (MOC)

Management of change (MOC) is a formal process for reviewing, approving and documenting changes to equipment, processes, materials, procedures or organization before they are made, so new hazards are identified and controlled. A good MOC process makes sure the right people assess the risk, update documents and train affected workers before the change goes live.

MOC is a required element of OSHA's Process Safety Management standard for facilities that handle highly hazardous chemicals, and it is a core requirement of ISO 45001. Many organizations outside those requirements also use MOC because uncontrolled change is a frequent factor in serious incidents.

What Is Management of Change (MOC)?

Under OSHA's 29 CFR 1910.119(l), employers covered by process safety management (PSM) must establish and implement written procedures to manage changes, except "replacement in kind," to process chemicals, technology, equipment and procedures, and changes to facilities that affect a covered process.

A replacement in kind is a replacement that satisfies the original design specification, such as swapping a pump for an identical model. Anything that does not meet the existing specification is a change and must go through MOC.

ISO 45001:2018 addresses the same idea in clause 8.1.3, Management of change, which requires organizations to plan and control temporary and permanent changes that affect occupational health and safety performance. The EPA Risk Management Program rule contains a parallel MOC requirement for covered facilities.

What counts as a change?

• Equipment and facilities: new or modified piping, vessels, controls, alarms, relief devices or building layouts.
• Process and technology: new chemicals or suppliers, changes to operating limits, flow rates, temperatures or pressures.
• Procedures: revised operating, maintenance or emergency procedures.
• Software and controls: changes to control logic, setpoints or safety instrumented systems.
• Organization: staffing reductions, new shift patterns, reorganized responsibilities or loss of experienced personnel. OSHA has issued an interpretation on management of organizational change noting that organizational changes can affect process safety and should be evaluated.
• Temporary changes: bypasses, temporary repairs or temporary equipment, which must be tracked and either removed or made permanent through MOC by a set date.

Key OSHA MOC Requirements

1910.119(l) requires MOC procedures to address the following considerations before any change is made:

1. The technical basis for the proposed change
2. The impact of the change on safety and health
3. Modifications to operating procedures
4. The necessary time period for the change
5. Authorization requirements for the proposed change

The standard also requires that:

• Employees involved in operating the process, and maintenance and contract employees whose job tasks will be affected, are informed of and trained in the change before start-up of the process or affected part of the process.
• Process safety information is updated when a change affects it.
• Operating procedures and practices are updated when a change affects them.

When a modification is significant enough to require a change in process safety information, PSM also requires a pre-startup safety review (PSSR) under 1910.119(i) to confirm construction meets design specifications, procedures are in place and training is complete.

Why Management of Change Matters

Change is necessary for any business, but every change can introduce hazards the original design never considered. A larger pump may exceed the rating of downstream piping. A new chemical may react with residue in shared equipment. A staffing change may leave no one on shift who knows how to respond to an abnormal condition.

MOC forces these questions to be asked before the change, when fixes are cheapest. It also keeps documentation accurate, so drawings, procedures and training reflect how the facility actually operates. Investigations of serious process incidents frequently find that a change was made without an adequate hazard review.

The MOC Process Step by Step

1. Request the change. The originator submits a request describing what will change, why and over what period. They state whether it is permanent, temporary or an emergency change.
2. Screen the request. A reviewer confirms whether it is a true change or a replacement in kind, and decides what level of review it needs.
3. Assess hazards and risk. A qualified team performs a risk assessment using methods such as a checklist, what-if analysis or HAZOP, depending on complexity.
4. Identify required actions. List the controls, document updates, training and inspections needed before start-up.
5. Authorize the change. Designated approvers sign off, typically including operations, engineering, maintenance and safety.
6. Implement the change. Carry out the work using normal safe work practices, such as a permit to work where required.
7. Train and communicate. Inform and train affected operators, maintenance staff and contractors before start-up.
8. Complete a pre-startup review. Verify that actions are closed and documents are updated.
9. Close out the MOC. Archive the record. For temporary changes, confirm removal or conversion to a permanent change by the expiry date.

Examples of Management of Change

• A plant replaces a carbon steel line with stainless steel of a different pressure rating. Because it is not a replacement in kind, the change requires a hazard review and updated piping specifications.
• A food processor switches to a new sanitizing chemical. The MOC review checks compatibility with equipment, updates the safety data sheet library and PPE requirements, and trains sanitation staff.
• A facility raises a reactor's operating temperature to increase throughput. The MOC confirms the new limit stays within design and updates alarms and operating procedures.
• A company reduces night shift staffing from four operators to three. The review assesses emergency response capability and workload before approving the change.

MOC vs. Related Processes

MOC vs. pre-startup safety review

MOC covers the full life of a change, from request to close-out. A PSSR is a checkpoint within that life that verifies readiness immediately before introducing hazardous materials or restarting.

MOC vs. document control

Document control manages versions of procedures and drawings. MOC decides whether a change is safe to make. A revised procedure may trigger MOC, and an approved MOC usually triggers document updates.

Common MOC Mistakes to Avoid

• Misusing replacement in kind to avoid review when the new item does not truly meet the design specification.
• Ignoring organizational and procedural changes and applying MOC only to hardware.
• Letting temporary changes become permanent without review because no one tracked the expiry date.
• Approving after the fact. An MOC completed after the change is installed defeats the purpose.
• Leaving actions open at start-up, such as training not delivered or drawings not updated.
• Making the process so burdensome that people work around it. Scale the review to the risk of the change.

Best Practices

Define clear triggers for MOC with examples employees can recognize. Use tiered review levels so minor changes move quickly while high-risk changes get a full team review. Assign a single owner to each MOC and track every action to closure. Audit a sample of completed MOCs each year to check quality, and include MOC performance, such as the number of overdue temporary changes, in your safety metrics.

How SMS360 Helps

SMS360's Management of Change module provides a structured workflow for submitting, reviewing and approving changes. Teams can attach risk assessments, assign actions to owners, record approvals and set reminders for temporary change expiry dates. Dashboards show open and overdue MOCs, and a complete record of each change is kept for audits and PSM compliance reviews.

Frequently Asked Questions

What is the OSHA requirement for management of change?

OSHA's Process Safety Management standard, 29 CFR 1910.119(l), requires covered employers to have written MOC procedures for changes to process chemicals, technology, equipment, procedures and facilities, other than replacement in kind. Procedures must address the technical basis, safety and health impact, procedure updates, time period and authorization. Affected employees must be informed and trained before start-up.

What is replacement in kind?

Replacement in kind is a replacement that satisfies the design specification of the item being replaced. Installing an identical valve or a spare that meets the same material, pressure and temperature ratings is replacement in kind and does not need MOC. If any specification differs, such as material, size, rating or function, the replacement is a change and must go through the MOC process.

When is a management of change required?

An MOC is required whenever a change to equipment, chemicals, technology, procedures, facilities or organization could affect safety and the change is not a replacement in kind. This includes temporary changes and emergency changes. Organizations not covered by PSM should still apply MOC to changes that could introduce new hazards, as recommended by ISO 45001 clause 8.1.3.

Who should approve an MOC?

Approvers depend on the type and risk of the change, but commonly include the operations manager responsible for the area, an engineering or technical authority, maintenance and the EHS lead. High-risk changes may also need site leadership approval. OSHA requires the procedure to define authorization requirements, so each organization should document who can approve which categories of change.