What this is
What is a machine modification review?
What is a machine modification review?
It is a structured check, carried out before a proposed change to a machine is made, that walks through what the change affects: guarding, interlocks, emergency stops, isolation points and the tasks operators and cleaners will do afterwards. It sits alongside the management of change (MOC) record rather than replacing it, and it exists specifically to stop safety-relevant side effects of a change being missed.
What counts as a modification rather than routine maintenance?
A modification is a change to how the machine is built, controlled or capable of operating: a mechanical alteration, a control system or software change, an added or removed guard, a capacity change, or a material change. Replacing a worn part with the same part to the same specification is maintenance. Changing the part, the control logic, or the way the machine is accessed is a modification, and this review applies.
How does this review relate to the management of change (MOC) record?
The MOC record is the administrative trail that a change was proposed, authorised and closed out. This review is the technical content that sits inside it: the specific safety questions about guarding, controls, isolation and training that the MOC process needs answered before the change is approved. The two are linked by ID so one cannot be signed off without reference to the other.
Scope
When is a machine modification review required?
This review covers the change itself and its immediate safety consequences. It does not replace the whole-of-life risk assessment, the guard verification, or the interlock test it may trigger — those are separate records this review points to.
Use this template when
- A mechanical, control, software, guarding, capacity or material change to a machine is being proposed
- The change needs sign-off before work starts, tied to a management of change (MOC) record
- You are running the Machine Safety programme and this is the change-control step within it
- The change may affect guarding, interlocks, emergency stops, isolation points or the tasks operators perform
- A linked record needs this one to exist: links Asset, MOC
Do not use it for
- Machine Risk Assessment, which assesses a machine across its whole life, including setup, running, cleaning, clearing jams and maintenance, rather than a single proposed change.
- Guarding Verification Checklist, which confirms that guards already fitted match the risk assessment and cannot be easily defeated — use it after this review triggers a verification, not instead of it.
- Interlock Function Test, which tests that an installed interlock actually stops the machine — this review only decides whether a test is required.
- Robot Cell Safety Assessment, which covers robot-specific hazards and cell layout, not general machine modifications.
- Anything outside KnowSafe, which belongs in the workspace that owns that process
Compliance mapping
Which ISO 45001 cl.8.1.3 requirements does this satisfy?
ISO 45001 cl.8.1.3 requires organisations to establish a process for managing change that could affect health and safety outcomes. The clauses below show where each part of that requirement lands inside this form.
| Clause | Requirement | Where it lands |
|---|---|---|
| ISO 45001 cl.8.1.3 | Management of change is planned and reviewed before the change is implemented | The modification |
| ISO 45001 cl.8.1.2 | Hazards created by the change are identified, and eliminated or controlled rather than merely noted | Safety effects |
| ISO 45001 cl.6.1.2 | The risk assessment is reviewed and updated to reflect any new or changed hazard | Requirements |
| ISO 45001 cl.7.5 | Documented information — drawings, manuals, procedures — is kept current with the modified machine | Requirements |
| ISO 45001 cl.7.2 | Workers are retrained where the change affects how they operate, clean or clear the machine | Requirements |
| ISO 45001 cl.8.1.1 | Operational controls — guarding and interlocks — are verified working before the machine returns to service | Requirements |
| ISO 45001 cl.10.2 | Actions arising from the review are recorded and tracked through to closure | Decision |
What it does not cover
- A modification description with no modification type selected, which leaves engineering unable to say whether mechanical, control, software or guarding risk applies.
- Guarding marked affected with no verification check ID entered, which leaves a guard change unconfirmed against the risk assessment it is supposed to satisfy.
- Interlocks or emergency stops marked affected but interlock test marked not required, which lets a control change go back into service without a functional test.
- Modification acceptable marked 'yes with conditions' and the conditions field left blank, which gives the sign-off no record of what has to happen before the machine runs.
- Action required marked yes with no CAPA ID raised, which leaves engineering with a documented decision and nothing tracking it to closure.
Global
Machine Modification Review requirements by country
A machine modification review sits at the intersection of a management system standard, a workplace safety regulator, and product conformity law — and the conformity question is the one most often missed.
ISO 45001 cl.8.1.3
Certifiable management-system requirement to plan and review changes affecting health and safety
Where a company holds or is pursuing ISO 45001 certification, an auditor will expect a documented, repeatable process for exactly this kind of change review — not an ad hoc engineering sign-off.
Machinery Directive 2006/42/EC / UK Supply of Machinery (Safety) Regulations 2008
Modifying a CE- or UKCA-marked machine can transfer manufacturer responsibility for its conformity to the company that made the change
This is why the form asks whether the original manufacturer was consulted and whether conformity status is affected before it asks anything about guarding — get this wrong and the modifying company may inherit obligations it never intended to take on.
OSHA 1910.212
General duty to guard the point of operation and moving parts
Any modification that touches guarding re-triggers this duty. A change that leaves a point of operation less guarded than before is a violation regardless of what the MOC record says was intended.
How to complete it
How to complete a machine modification review, step by step
Filling in the fields is mechanical. The judgement calls below are what actually determine whether the sign-off holds up later.
Not every modification needs the original manufacturer's input, but a change to control logic, capacity or a safety-related component usually does. Marking 'original manufacturer consulted' as N/A on anything beyond a cosmetic change is the decision most likely to be challenged if the machine is later involved in an incident.
'Not required' is a valid answer only when the change genuinely does not alter risk — a like-for-like part swap dressed up as a modification, for instance. Anything that changes reach, access, energy isolation or hazard exposure needs the risk assessment reopened, not annotated.
Operator retraining marked 'yes' but scheduled for 'whenever the next refresher falls due' is functionally a 'no' for the period in between. If the change alters how the machine is cleared, cleaned or cleared of jams, retraining has to happen before the machine returns to normal running, not on the training calendar's schedule.
'Yes with conditions' is only as strong as the conditions text. A vague condition like 'monitor after restart' cannot be verified by anyone else later; a specific one like 'interlock test SAF-094 must close before first production run' can. Treat vague conditions as equivalent to no conditions at all.
What auditors find
Most common machine modification review findings
Patterns that turn up repeatedly when these reviews are checked after the fact, and what closes each gap.
| Finding | Clause | What fixes it |
|---|---|---|
| Guarding marked not affected, but the modification narrative describes removing a panel for access | ISO 45001 cl.8.1.2 | Re-inspect the guarding after the work is complete and correct the answer against what was actually done, not what was planned. |
| Conformity status marked 'possibly' with no manufacturer consultation recorded | EU Machinery Directive 2006/42/EC | Escalate to the manufacturer or a competent body before the machine returns to service — 'possibly' is not a closed answer. |
| Interlock test marked N/A on a change that also changed isolation points | ISO 45001 cl.8.1.1 | Treat any isolation point change as an automatic trigger for an interlock test, regardless of what the interlock-affected field says. |
| Risk assessment marked 'not required' on a permanent modification | ISO 45001 cl.6.1.2 | Reserve 'not required' for temporary changes with a defined review date; permanent changes always update the risk assessment. |
| Drawings and manuals left at 'partial' with no follow-up action raised | ISO 45001 cl.7.5 | Raise a CAPA whenever documentation is marked partial or fail — a partial update left unrecorded becomes a permanent gap. |
| Modification approved with conditions but no action or CAPA record exists | ISO 45001 cl.10.2 | Require an action record for every 'yes with conditions' decision, so the condition has somewhere to be tracked to closure. |
Case in point
Case in point: the interlock that was never retested
A packing line conveyor had its guard door relocated to speed up changeover access. The modification review recorded guarding as affected and interlocks as affected, and correctly required an interlock test. The test was scheduled but the machine was returned to production the same afternoon, before the test record existed, because the changeover deadline was tighter than the safety sign-off.
Three weeks later the relocated door was found to trip the interlock inconsistently, sometimes allowing the conveyor to run with the door open. Nothing in the modification review was wrong — the guarding, interlock and test-required fields were all answered correctly. The gap was operational: a record marked 'required' was treated as equivalent to 'complete' under production pressure, and nothing in the process stopped the machine running in between.
The template
The template, field by field
The form exactly as it installs. Every field, option, score and conditional rule is editable, and the links to other templates come with it.
5 sections
- Reference
- SAF-097
- Archetype
- Review
- Record ID
- MREV-2026-000
- Scoring
- Risk band
- Direction
- High is bad
- Singleton
- No
- Basis
- ISO 45001 cl.8.1.3
- Links
- Links Asset, MOC
- Tags
- Machine, Change
- Sections
- 5
- Fields
- 42
- Follow up fields
- 3
- Repeating sections
- 0
- Links out
- 6
Header
9 fieldsReview ID*
Auto sequence. Format MREV-2026-000.
The record's own ID. Other templates point at this value.
Status*
Drives who this goes to next.
- Planned2 pts
- In progress2 pts
- Complete3 pts
- Deferred0 pts
- Open0 pts
- Closed3 pts
- Overdue0 pts
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Review Date*
Reviewed By*
MOC ID*
Links to FDN-020 MOC ID
Machine*
Asset ID*
Format AST-0000.
Links to FDN-002 Asset ID
The modification
5 fieldsModification Description*
Modification Type*
Mechanical, control system, software, guarding, capacity or material change.
Permanent Or Temporary*
- Temporary with review date3 pts
- Permanent1 pt
Original Manufacturer Consulted*
Modifying a machine can transfer manufacturer responsibility to you.
- Pass2 pts
- Partial1 pt
- Fail0 pts
- N/Aexcluded from denominator
CE Or Conformity Status Affected*
- No3 pts
- Possibly1 pt
- Yes0 pts
Safety effects
10 fieldsWhat Gets Removed
The most common machine modification failure is a guard taken off for access during the change and never refitted. Check the guarding after, not just before.
Guarding Affected*
- No3 pts
- Yes0 pts
Interlocks Affected*
- No3 pts
- Yes0 pts
Emergency Stops Affected*
- No3 pts
- Yes0 pts
Isolation Points Changed*
- No3 pts
- Yes0 pts
Energy Control Procedure Needs Updating*
- Pass2 pts
- Partial1 pt
- Fail0 pts
- N/Aexcluded from denominator
Reach Or Access Changed*
- No3 pts
- Yes0 pts
New Hazards Introduced*
- None3 pts
- Some1 pt
- Significant0 pts
Cleaning Method Affected*
- No3 pts
- Yes0 pts
Food Contact Surfaces Affected*
- No3 pts
- Yes0 pts
Requirements
8 fieldsRisk Assessment Updated*
- Yes3 pts
- Not required3 pts
- No0 pts
Risk Assessment
Risk ID
Format RSK-2026-00000.
Links to FDN-012 Risk ID
Guarding Verification Required*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Verification Check ID
Links to SAF-093 Check ID
Interlock Test Required*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Operator Retraining Required*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Drawings And Manuals Updated*
- Pass2 pts
- Partial1 pt
- Fail0 pts
- N/Aexcluded from denominator
Decision
10 fieldsModification Acceptable*
- Yes3 pts
- Yes with conditions2 pts
- No0 pts
Conditions
Action Required*
Raise the action record, then enter its reference here.
- No2 pts
- Yes0 pts
Priority
- High0 pts
- Medium1 pt
- Low3 pts
CAPA ID
Format CAPA-2026-00000.
Links to FDN-014 CAPA ID
Action Owner
Reviewed By*
Signature*
Engineering Manager*
Second Signature*
SAF-097 · record IDs look like MREV-2026-000 · Links Asset, MOC
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The form captures the decision. Keeping the linked risk assessment, guarding verification and training records actually current is the part that erodes without a system watching it.
Holds the modification review against the asset and risk assessment registers, and won't let a 'yes with conditions' decision go quiet without a linked action.
Sees the same asset's work order and maintenance history, so a modification and a maintenance job on the same machine don't get logged as two unrelated events.
Rolls the management-of-change trail into the ISO 45001 evidence pack, so an auditor asking for cl.8.1.3 evidence gets a real answer instead of a scramble.
Coordinates the crew, rolls completion and exceptions into one view, and holds every write for your approval before it touches a record.
This template lives in KnowSafe — safety and compliance. Incidents, hazards, permits, inspections and the critical controls behind them.
Meet KnowSafe→Glossary
Machine Modification Review definitions and key terms
- Management of change (MOC)
- The administrative process and record confirming that a proposed change was reviewed, authorised, implemented and closed out in a controlled way, rather than made informally.
- CE / UKCA marking
- The conformity mark showing a machine meets applicable EU or UK machinery safety requirements. Modifying a marked machine can shift responsibility for that conformity onto the modifier.
- Isolation point
- A point at which energy — electrical, pneumatic, hydraulic or mechanical — can be positively cut off from a machine, used during lockout/tagout.
- Point of operation
- The location on a machine where work is actually performed on the material — cutting, forming, pinching — and where guarding duties are strictest.
- Interlock
- A device that prevents a machine from operating, or stops it, when a guard is open or removed. A modification that changes access can silently defeat an existing interlock's coverage.
FAQ
Frequently asked questions about machine modification review
Does every machine change need a full modification review?+
Every change that alters how the machine is built, controlled or accessed does. A genuine like-for-like part replacement, made to the original specification, is maintenance and does not need this review — but if there is any doubt about whether a change is 'like-for-like', run the review.
What happens if the manufacturer can't be consulted?+
Record that consultation was attempted and why it wasn't possible, then route the conformity question to a competent person or body instead. Marking the field as N/A without an alternative check is the gap most likely to surface in a later incident investigation.
Can the machine run again before the follow-up actions are closed?+
Only if the modification is marked acceptable outright. Where it is marked 'yes with conditions', the conditions define what must be true before or during the return to service — the machine should not run ahead of them regardless of production pressure.
Who has to sign off a machine modification review?+
The reviewer and a second signature from the engineering manager, reflecting that this decision carries enough weight to need independent confirmation, not a single sign-off.
How does this link to the risk assessment and guarding verification?+
The review references the relevant risk assessment and, where guarding verification or an interlock test is triggered, carries the check ID for that record. None of those linked records replace this review — they close out what it opens.
Can the modification review template be changed?+
Yes. Every field, option, score and conditional rule is editable, and the links to other templates come with it. Most teams install it as it is, run it for a cycle, then adjust.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Machine Safety
Lockout/Tagout Procedure (Machine Specific)
Sets out exactly how to isolate a specific machine, listing every energy source and isolation point
LOTO Periodic Inspection
Checks that a specific energy control procedure is being followed correctly in practice
Machine Risk Assessment
Assesses a machine across its whole life, including setup, running, cleaning, clearing jams and maintenance
Guarding Verification Checklist
Confirms that guards fitted to a machine match the risk assessment and cannot be easily defeated
Interlock Function Test
Tests that safety interlocks stop the machine when a guard is opened, and cannot be bypassed
Robot Cell Safety Assessment
Assesses an industrial or collaborative robot cell, covering reach, speed, force limits and how people enter the space
More in Machine Safety
Machine Risk Assessment
Assesses a machine across its whole life, including setup, running, cleaning, clearing jams and maintenance
Guarding Verification Checklist
Confirms that guards fitted to a machine match the risk assessment and cannot be easily defeated
Interlock Function Test
Tests that safety interlocks stop the machine when a guard is opened, and cannot be bypassed
Robot Cell Safety Assessment
Assesses an industrial or collaborative robot cell, covering reach, speed, force limits and how people enter the space
Pinch Point Survey
Walks a machine or line looking specifically for pinch, nip, shear and crush points
Emergency Stop Test Record
Tests that emergency stops actually stop the machine and are reachable from where people work
Written and reviewed by
Siddarth Singh
Founder & Chief Executive Officer, Knowella
Certified Safety Professional and industrial and systems engineer with more than a decade inside food supply chain, freight and manufacturing operations. This page was written against the current text of the standards it cites, not against secondary summaries of them.
- Certified Safety Professional (CSP), Board of Certified Safety Professionals
- MBA, University of Chicago Booth School of Business
- MS and BS, The Ohio State University, Industrial and Systems Engineering
- Six Sigma Black Belt
Sources and last review. Reviewed 16 August 2026 against:
- ISO 45001 cl.8.1.3 — Management of change
- ISO 45001 cl.8.1.2 — Eliminating hazards and reducing OH&S risks
- OSHA 1910.212 — Machine guarding general requirements
- Machinery Directive 2006/42/EC
- UK Supply of Machinery (Safety) Regulations 2008
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.