What this is
What is a backlog review?
What is a backlog review?
It is a periodic review of every outstanding work order, broken down by age, priority, asset and cause, run inside KnowMaintain's Planned Maintenance programme. It is built against ISO 55001 cl.9.1, which requires asset performance to be measured against defined criteria at defined intervals.
What counts as ready backlog versus waiting backlog?
Ready backlog is work that has parts, permits and a plan already in place and could start today if labour were available. Waiting backlog is blocked on one of those. The distinction matters because only ready backlog tells you anything about labour capacity — waiting backlog is a planning or supply problem, not a staffing one.
Why review backlog weekly instead of monthly?
Backlog on critical assets can move from manageable to unsafe within a few weeks, and a monthly cycle catches it too late for the ready backlog figure to still be current. A weekly cadence keeps the trend column meaningful rather than reactive.
Scope
When is a backlog review required?
This review looks at the outstanding work order population as a whole, at a point in time. It does not create or close individual work orders, and it does not investigate a single asset's history — those belong to the records this one reviews.
Use this template when
- The review interval has come round, on the cadence the plant has set for it
- A trigger event — a spike in emergency work, a critical asset failure — calls for an off-cycle review
- A new record is needed; each one gets its own ID in the form BLR-2026-000
- You are running the Planned Maintenance programme and this is one of its steps
- Work orders need to be traced back from this review; links work orders
Do not use it for
- Work Order, which is the individual job this review counts and ages, not a summary of many.
- Schedule Compliance Review, which asks whether planned work happened on time, a different question from how much work is waiting.
- Maintenance Backlog Review, which covers the same ground at a different reporting level within the same programme; confirm which one your site standardises on before running both.
- Maintenance Cost Review, which looks at spend rather than the volume and age of outstanding work.
- Anything outside KnowMaintain, which belongs in the workspace that owns that process.
Compliance mapping
Which ISO 55001 cl.9.1 requirements does this satisfy?
ISO 55001's performance evaluation clause requires the organisation to monitor and measure asset management performance at planned intervals — a backlog review is one of the standard ways plants satisfy that requirement for maintenance execution specifically.
| Clause | Requirement | Where it lands |
|---|---|---|
| ISO 55001 cl.9.1 | Asset management performance must be monitored, measured and evaluated at defined intervals against criteria the organisation has set. | Backlog volume |
| ISO 55001 cl.9.1 | The measurement method must distinguish planned, corrective and emergency work so a shift between categories is visible, not averaged away. | Composition |
| ISO 55001 cl.6.1 | Risks to achieving asset management objectives must be identified — backlog on critical assets and open safety-related orders are the primary risk signal this review carries. | Critical assets |
| ISO 55001 cl.8.1 | Operational controls must ensure planned criteria are met and deviations are managed, which is why a constraint has to be named whenever backlog is high. | Constraints |
| ISO 55001 cl.10.1 | Where performance evaluation identifies a nonconformity, corrective action must be raised and tracked to closure. | Constraints |
| ISO 55001 cl.7.5 | Documented information supporting the asset management system must be retained and traceable, including the specific work orders a review draws its conclusions from. | Related records |
| ISO 55001 cl.5.3 | Roles and authorities for reporting on performance must be assigned, reflected here in the planner's and maintenance manager's joint sign-off. | Constraints |
What it does not cover
- Ready Backlog Weeks, which is left blank while only the combined Backlog In Weeks figure is filled in.
- Emergency Percent, which is recorded above 20 percent with no constraint or action named anywhere in the record.
- Backlog On Critical Assets and Safety Related Work Orders Open, which are both non-zero but Action Required is marked No.
- Main Constraint, which is left unset even though the trend is marked Worsening.
- Signature and Second Signature, which are missing, leaving the review unagreed by planning and maintenance management.
Global
Backlog Review requirements by country
As with the rest of the asset management templates, ISO 55001 carries no statutory force on its own — its authority in a backlog review comes from certification schemes, customer contracts, and how directly the backlog touches safety or food-safety obligations that are legally binding regardless of ISO status.
ISO 55001:2014, alongside HSE's general duty under the Health and Safety at Work etc. Act 1974
A UK site with safety-related orders in backlog carries exposure under general health and safety duty regardless of ISO certification, which is why Safety Related Work Orders Open is tracked as its own figure rather than folded into the general count.
An HSE inspector reviewing an incident will ask whether a safety-related order was known and outstanding — a review that recorded it but showed no action is worse evidence than not tracking it at all.
No federal ISO mandate; OSHA general duty clause and food-safety-linked FSMA preventive controls where applicable
ISO 55001 adoption in the US is customer- or insurer-driven, but Food Safety Related Open counts intersect FSMA preventive-controls obligations directly in food manufacturing sites, giving that single field legal weight the rest of the review doesn't carry.
A backlog review can be entirely informal for general maintenance purposes and still need Food Safety Related Open tracked rigorously, because that figure may be requested in a regulatory or customer audit independent of the wider ISO framework.
ISO 55001:2014 certification and buyer vendor-qualification audits
Multinational buyers auditing a supplier's asset management system sample backlog trend data directly, since a worsening trend with no named constraint is one of the clearest signs maintenance is losing ground to production.
A review with no Trend Versus Last Period, or one marked Worsening with no Actions Agreed, is exactly what a supplier audit is designed to surface.
How to complete it
How to complete a backlog review, step by step
The mechanics of counting open work orders are simple. The judgement is in deciding which numbers to trust and what they're actually telling the plant.
Ready Backlog Weeks only means something if someone has checked that parts, permits and plans are actually in place, rather than assuming anything not obviously blocked is ready. A planner estimating this from memory instead of the CMMS status field will consistently overstate ready backlog and understate the labour shortfall it's meant to reveal.
Crossing twenty percent emergency work is worth treating as a trigger in itself, not just a number to report. The judgement call is whether this period's spike is a one-off or the start of a pattern — that's what Trend Versus Last Period is for, and it should be judged against the prior two or three reviews, not just the immediately preceding one.
An improving overall trend can mask a worsening critical-asset picture if the reduction came from clearing easy, low-priority work while critical-asset backlog held steady or grew. Check Backlog On Critical Assets against the trend independently, not as if it moves the same way.
Action Required separates 'we discussed it' from 'someone owns fixing it by a date.' Resist marking No just because the constraint is well understood — a known, chronic constraint with no CAPA against it is exactly the pattern this field is meant to stop.
What auditors find
Most common backlog review findings
The same handful of gaps show up review after review, almost always because the volume figures were filled in but the composition and constraint fields were treated as optional commentary.
| Finding | Clause | What fixes it |
|---|---|---|
| Backlog In Weeks is reported but Ready Backlog Weeks is left blank. | ISO 55001 cl.9.1 | Make Ready Backlog Weeks a required field alongside the total, since the total alone can't distinguish a labour shortage from a planning blockage. |
| Emergency Percent exceeds 20 percent with no Main Constraint recorded. | ISO 55001 cl.8.1 | Force Main Constraint to be set whenever Emergency Percent crosses the threshold, so the review can't pass the figure through silently. |
| Safety Related Work Orders Open is non-zero but Action Required is marked No. | ISO 55001 cl.6.1 | Force Action Required to Yes whenever Safety Related Work Orders Open or Food Safety Related Open is above zero, removing the option to wave it through. |
| Trend Versus Last Period is marked Worsening with no Actions Agreed text entered. | ISO 55001 cl.10.1 | Require a minimum entry in Actions Agreed whenever the trend is Worsening, so the review captures what's changing before the next cycle rather than just naming the direction. |
| Oldest Open Work Order Days is high but no representative Work Order ID is linked in Related records. | ISO 55001 cl.7.5 | Require a linked Work Order ID whenever Work Orders Over 90 Days Old is greater than zero, so the review traces back to an actual record, not just a summary figure. |
| The review closes with only the Planner's signature, no Maintenance Manager sign-off. | ISO 55001 cl.5.3 | Block closure until both signatures are present, matching the joint accountability the record is designed to enforce. |
Case in point
Case in point: the backlog that looked stable for three months
A plant's weekly backlog review reported Backlog In Weeks holding steady at five for three straight months — a healthy, unremarkable figure. Nobody escalated it. Underneath, Emergency Percent had drifted from eleven to twenty-three percent, and Backlog On Critical Assets had gone from one open order to four, both absorbed into a total that stayed flat because low-priority routine work was being cleared faster to compensate.
The pattern surfaced only when a supervisor cross-checked Composition against three prior records instead of just the current one. By then, two of the four critical-asset orders were past ninety days old. The fix wasn't a new field — every number needed had already been captured — it was a standing instruction that Trend Versus Last Period be judged against the last three reviews, not the most recent one, before it could be marked Stable.
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.
6 sections
- Reference
- MNT-012
- Archetype
- Review
- Record ID
- BLR-2026-000
- Scoring
- Backlog weeks
- Direction
- High is bad
- Singleton
- No
- Basis
- ISO 55001 cl.9.1
- Links
- Links Work Orders
- Tags
- Maintenance, Governance
- Sections
- 6
- Fields
- 42
- Follow up fields
- 3
- Repeating sections
- 0
- Links out
- 3
Header
12 fieldsReview ID*
Auto sequence. Format BLR-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
Date and Time*
Raised By*
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Area
The area within the site.
Exact Location
Drop a pin for anything hard to find.
Period From*
Period To*
Reviewed By*
Backlog Is A Leading Indicator
A backlog growing on critical assets is the clearest early warning that a plant is heading for trouble. Four to six weeks of ready backlog is healthy. Zero means you are purely reactive.
Backlog volume
6 fieldsOpen Work Orders*
Total Estimated Hours*
Weekly Available Hours*
Backlog In Weeks*
Ready Backlog Weeks*
Work with parts, permits and plans in place. This is the number that matters.
Waiting Backlog Weeks
Composition
6 fieldsPreventive Percent*
Corrective Percent*
Emergency Percent*
Above 20 percent emergency means the plant is running you rather than the other way round.
Work Orders Over 90 Days Old*
Oldest Open Work Order Days*
Work Orders With No Owner*
Critical assets
5 fieldsBacklog On Critical Assets*
Safety Related Work Orders Open*
Food Safety Related Open*
Temporary Repairs Outstanding*
Temporary Repairs Past Due*
Related records
1 fieldWork Order ID
A representative overdue order from the backlog.
Links to MNT-002 Work Order ID
Constraints
12 fieldsMain Constraint*
Labour, parts, access windows, permits, contractor availability or planning.
Trend Versus Last Period*
- Improving3 pts
- Stable2 pts
- Worsening0 pts
Actions Agreed
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
Next Review Due*
Planner*
Signature*
Maintenance Manager*
Second Signature*
MNT-012 · record IDs look like BLR-2026-000 · Links Work Orders
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The review surfaces the numbers. What determines whether backlog actually gets managed is whether the pattern is caught early enough for a constraint to be fixed before it becomes a failure.
Tracks backlog composition against the asset register and work order history, and flags when Emergency Percent or critical-asset backlog crosses a threshold with no constraint recorded.
Watches Safety Related Work Orders Open and Food Safety Related Open specifically, and escalates independently of the overall backlog trend when either sits above zero.
Cross-checks temporary repairs past due and food-safety backlog against the same nonconformance register that customer complaints and audit findings feed.
Compares this review against the last three cycles, not just the prior one, flags a drifting composition under a stable headline figure, and holds every write for approval before it touches a record.
This template lives in KnowMaintain — asset maintenance. Work orders, planned maintenance, calibration, reliability and shutdowns.
Meet KnowMaintain→Glossary
Backlog Review definitions and key terms
- Ready backlog
- Outstanding work with parts, permits and a plan already in place, limited only by labour — the figure that actually measures staffing capacity against demand.
- Waiting backlog
- Outstanding work blocked on something other than labour, such as parts, permits or an access window — a planning or supply signal, not a staffing one.
- Emergency work
- Unplanned work that must start immediately, bypassing normal scheduling; a rising share indicates the plant is running reactively rather than to plan.
- Backlog weeks
- Total outstanding estimated hours divided by weekly available labour hours, expressing the backlog as a duration rather than a raw count.
- Critical asset
- An asset whose failure carries a disproportionate safety, food-safety or production consequence, and whose backlog is tracked separately from the general population for that reason.
FAQ
Frequently asked questions about backlog review
What is a healthy backlog-in-weeks figure?+
This template is built around four to six weeks of ready backlog as the healthy range. Zero means the plant has no buffer and is purely reactive; a much larger number usually means planning is generating work faster than the crew can execute it.
Why review weekly rather than monthly?+
Backlog on critical assets and emergency-work percentage can shift meaningfully within a few weeks. A monthly cadence catches the trend too late to act on it inside the same reporting period; weekly reviews keep the trend column reflecting current conditions.
Does every backlog review need a CAPA raised?+
No. Action Required should reflect whether something genuinely needs a tracked corrective action versus routine, expected variation. Forcing a CAPA every review dilutes the signal for the ones that actually need escalation.
How is this different from Maintenance Backlog Review or Schedule Compliance Review?+
This review covers the outstanding work order population's volume, composition and age. Schedule Compliance Review asks whether planned work happened on time. Maintenance Backlog Review covers similar ground at a different reporting level — confirm which is your site's system of record before running both.
What if Main Constraint changes every review?+
That's useful in itself — a constraint that never repeats suggests the plant is reacting to whatever surfaced that week, not a structural bottleneck. A constraint that repeats across reviews with no action against it is the pattern worth escalating.
Who needs to sign off the review?+
The Planner and the Maintenance Manager both sign. The review is designed as a joint planning-and-management artefact, not a planner's private tracking sheet, which is why both signatures are required before it closes.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Planned Maintenance
Asset Register
Holds every piece of equipment, machine, vehicle and tool you track
Tool and Equipment Register
Holds portable tools, gauges, lifting accessories and small equipment that sit below asset level but still need control
Maintenance Request
Asks maintenance to look at a problem or carry out a job
Work Order
The main record for a planned maintenance job, covering what, where, who and when
Corrective Work Order
Covers a repair to fix something that has already failed or degraded
Emergency Work Order
Covers urgent work where equipment has stopped or become unsafe
More in Work Orders
Maintenance Request
Asks maintenance to look at a problem or carry out a job
Work Order
The main record for a planned maintenance job, covering what, where, who and when
Corrective Work Order
Covers a repair to fix something that has already failed or degraded
Emergency Work Order
Covers urgent work where equipment has stopped or become unsafe
Work Order Closeout
Confirms the job is finished, the area is safe and the equipment is fit to run
Job Plan
Sets out the steps, parts, tools, permits and time needed for a repeatable job
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 55001:2014 cl.9.1 — Monitoring, measurement, analysis and evaluation
- ISO 55001:2014 cl.6.1 — Actions to address risks and opportunities
- ISO 55001:2014 cl.10.1 — Nonconformity and corrective action
- Health and Safety at Work etc. Act 1974 — general duty of care
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.