Running an asset criticality assessment that holds up
Most registers carry a criticality column. Fewer can defend how it was set. How consequence and likelihood are actually scored, the workshop that sets them, and what each band should change.
Key takeaways
- Criticality is consequence and likelihood in the asset's real operating context, so the same pump can sit in different bands in different services.
- Scales need anchors: consequence bands tied to real production, safety and cost outcomes, not adjectives.
- The output is bands that change something. A ranked list that changes nothing is a spreadsheet, not an assessment.
- Revisit on triggers, duty change, configuration change and incidents, or the ranking quietly ages into fiction.
Nearly every asset register carries a criticality column. Ask how it was set and the answers get vague: a workshop years ago, a contractor's template, a copy from another site. Yet that column quietly decides where analysis effort, monitoring spend and spares money go.
Run properly, a criticality assessment is the cheapest high-leverage exercise in asset management: a few weeks of structured work that directs years of investment, and it is the ranking the asset management plan leans on to keep spending proportionate. Run loosely, it launders opinion into a number.
What criticality actually measures
Criticality is the product of consequence and likelihood for an asset in its operating context. Consequence spans safety, environment, production and cost, and it belongs to the service the asset performs rather than the asset itself. The same pump model is critical in unspared crusher lubrication duty and nearly irrelevant as one of three in parallel.
That context dependence is why copied rankings fail. A register imported from another site imports another site's operating context with it.
Getting the scales right
Consequence bands need anchors the operation recognises: hours of lost production and what they are worth, defined safety and environmental outcomes, repair cost thresholds. Adjective scales, minor through catastrophic, produce arguments because every participant carries a different dictionary.
Likelihood is scored from failure history where the coding supports it, and from the experience in the room where it does not. Precision matters less than consistency, because a ranking is comparative: it only has to be honest in the same way for every asset. The Criticality Matrix Calculator lays out an anchored 5×5 scale to adapt, with a register template to download.
A criticality score is a comparison, not a measurement. It works as long as it is wrong the same way everywhere.
Running the workshop
- Score system by system, not tag by tag: rank at the level where consequence is felt, then inherit downwards.
- The room needs operations, maintenance and engineering together. Any one group alone scores its own fears.
- Fix the scales and definitions before the first asset is scored, and do not renegotiate them mid-exercise.
- Record the reasoning, not just the score, because the why is what the next review needs.
- Timebox it. A criticality workshop that runs for months is doing RCM badly by accident.
From bands to actions
The ranking earns its keep only when each band changes what happens next. A workable pattern:
| Band | Strategy depth | What else changes |
|---|---|---|
| Highest | Full FMECA and RCM decision logic | Condition monitoring justified, engineered spares, review on every incident |
| Middle | Template strategies tuned per equipment class | Monitoring by exception, spares set from lead time and pooling |
| Lowest | Run-to-failure where that is honest | Minimal stocking, no scheduled intrusive work |
Where assessments go wrong
- Everything lands in the top band, because nobody wants their equipment ranked second.
- Scores exist but no action is attached to a band, so nothing changes.
- One engineer scores the plant alone: quickly, consistently, and wrong.
- The assessment is never revisited, so years of plant changes accumulate against a frozen ranking.
If everything is critical, the ranking is measuring politics, not risk.
How an assessment runs
Set the scales
Consequence and likelihood bands anchored to real production, safety and cost outcomes.
Assemble the data
Hierarchy, spares, history and operating context, at the level where consequence is felt.
Workshop the ranking
Operations, maintenance and engineering score together against fixed definitions.
Band and assign
Each band drives strategy depth, monitoring investment and spares decisions.
Govern
Review triggers for duty, configuration and incidents keep the ranking current.
Set the scales
Consequence and likelihood bands anchored to real production, safety and cost outcomes.
Assemble the data
Hierarchy, spares, history and operating context, at the level where consequence is felt.
Workshop the ranking
Operations, maintenance and engineering score together against fixed definitions.
Band and assign
Each band drives strategy depth, monitoring investment and spares decisions.
Govern
Review triggers for duty, configuration and incidents keep the ranking current.
Common questions
How many criticality bands should we use?
Three to five. What matters is that each band drives a different action: analysis depth, monitoring investment, spares stocking. More bands than distinct actions is false precision.
Do we need clean failure history first?
It helps likelihood scoring but it is not a precondition. Consequence, which does most of the work, can be scored from operating knowledge. Start with the knowledge in the room and refine likelihood as coding improves.
How often should criticality be reassessed?
On triggers rather than a calendar alone: duty or throughput changes, configuration changes and incidents, with a periodic sweep to catch drift. An assessment left static stops describing the plant.
Key terms
Plain-language definitions from our glossary for the concepts this article leans on.
Standards and further reading
- SAE JA1011 Evaluation criteria for RCM processes (SAE International)
- ISO 14224:2016 Collection and exchange of reliability and maintenance data for equipment (ISO)
- ISO 55001:2024 Asset management system requirements (ISO)
- Best practices, metrics and guidelines for maintenance and reliability (SMRP)
- The Asset Management Landscape, third edition (GFMAM)
- Asset Management Council, Australian asset management community (Asset Management Council)
Related case studies and tools
- Reliability engineering and asset strategy program (case study)
- Predictive maintenance and condition monitoring (case study)
- Cost of Downtime Calculator (tool)
- Asset management planning and the system behind it (case study)
- Criticality Matrix Calculator (tool)
- Mining solutions (solution)
- Agriculture solutions (solution)
Related reading
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