Running an asset criticality ranking exercise
An asset criticality ranking exercise scores every piece of equipment by the consequence of its failure — on safety, environment, production and cost — to produce a prioritised register. It is the foundation step that tells a plant where to focus monitoring, spares and maintenance effort first.
What it is
Criticality ranking turns a flat equipment list into a prioritised one. A consistent scoring matrix rates each asset on the severity and likelihood of failure consequences, yielding a ranked register that drives every downstream reliability decision.
Why it is done
Maintenance resources are finite, so they must concentrate on assets whose failure hurts most. Without a criticality ranking, monitoring and spares are spread evenly — over-protecting trivial equipment and under-protecting the assets that can stop production or cause harm.
How it is done
A scoring matrix is agreed for safety, environmental, production and cost consequences, plus failure likelihood. A cross-functional team scores each asset against the matrix, the scores are combined into a criticality class, and the ranked register is used to assign monitoring intensity, spares holding and maintenance strategy. The ranking is revisited as the plant or its risks change.
- Agree scoring matrix
- List all assets
- Score consequences
- Score likelihood
- Rank & classify
- Assign strategy
What to watch for
Inconsistent scoring between teams undermines the whole ranking, so a single facilitated standard matters. A ranking that is never revisited becomes misleading as processes and risks evolve.
Related practices
Transitioning to condition-based maintenance
Rolling out reliability-centred maintenance
Running a defect elimination programme
Related topics
Asset Criticality · Condition-Based Maintenance (CBM)
Common in: Power Generation · Chemicals · Steel & Metals · Cement · Paper & Packaging · Pharmaceuticals