How do you calculate a critical asset downtime risk score?

Multiply the consequence severity, failure likelihood, and control-weakness scores together. With scores of 10, 5, and 4 on the appropriate scale, the result is a risk score of 6.75.

What is a good or bad downtime risk score?

Lower is better. There's no universal cutoff — set thresholds for your own scale and rank assets relative to each other, flagging the top tier (highest scores) for intervention rather than chasing an absolute number.

Why multiply the three factors instead of averaging them?

Multiplication makes a high score in any one factor amplify the others, so a severe, poorly detected failure stands out sharply. Averaging would dilute that signal and let a dangerous gap hide behind two moderate scores.

What does the control-weakness factor represent?

It rates how poorly your monitoring and contingency controls catch or buffer a failure — weak detection and no backup score high (worse), strong condition monitoring with redundancy score low (better). It's the inverse of FMEA detection capability.

Critical asset downtime risk vs FMEA RPN — what's the relationship?

This is RPN applied to asset downtime: severity x occurrence x detection, where 'detection' here is framed as control weakness. The structure is identical, so FMEA scoring discipline carries straight over.

How do I use the score to prioritize maintenance spend?

Rank every asset by score and attack the top of the list first — add condition monitoring, stock critical spares, or tighten PMs there. Reducing any one factor (better detection, redundancy, more frequent PM) lowers the score multiplicatively.

CMMS, EAM & Spare Parts Management calculator

Critical Asset Downtime Risk Calculator

Critical Asset Downtime Risk produces an RPN-style risk score for an asset by multiplying the severity of a downtime event, the likelihood it occurs, and how weak your monitoring and contingency controls are at catching or buffering it. Reliability engineers and maintenance managers use it to rank assets so finite PM, condition-monitoring, and spare-parts dollars flow to the equipment that would hurt most if it stopped. Unlike a gut-feel criticality call, the three-factor product surfaces the hidden danger: a high-consequence asset that's also poorly monitored scores far worse than its failure rate alone would suggest. Applied consistently across an asset register, it turns a vague 'everything's critical' list into a defensible priority ranking.

What this calculator does

Score downtime risk for critical assets using consequence, likelihood of failure, and weakness of detection or mitigation controls.
a maintenance or asset-management team needs to prioritize condition monitoring, critical spares, PM changes, and contingency planning for a critical asset risk review
It computes a single downtime risk score as the product of consequence severity, failure likelihood, and control weakness on a common scale.

Formula used

Critical Asset Downtime Risk risk score = downtime consequence severity score × failure or downtime likelihood score × weakness of monitoring and contingency controls
Use the same scoring scale across comparable assets, work orders, parts families, and maintenance risk reviews.

Inputs explained

Downtime consequence severity score:
Failure or downtime likelihood score:
Weakness of monitoring and contingency controls:

How to use the result

Use it during asset criticality reviews, FMEA-style assessments, or when prioritizing where to add condition monitoring and critical spares.
The multiplicative score compresses information — two assets can share a score for very different reasons, so always inspect the individual factors before acting.

Common questions

How do you calculate a critical asset downtime risk score? Multiply the consequence severity, failure likelihood, and control-weakness scores together. With scores of 10, 5, and 4 on the appropriate scale, the result is a risk score of 6.75.
What is a good or bad downtime risk score? Lower is better. There's no universal cutoff — set thresholds for your own scale and rank assets relative to each other, flagging the top tier (highest scores) for intervention rather than chasing an absolute number.
Why multiply the three factors instead of averaging them? Multiplication makes a high score in any one factor amplify the others, so a severe, poorly detected failure stands out sharply. Averaging would dilute that signal and let a dangerous gap hide behind two moderate scores.
What does the control-weakness factor represent? It rates how poorly your monitoring and contingency controls catch or buffer a failure — weak detection and no backup score high (worse), strong condition monitoring with redundancy score low (better). It's the inverse of FMEA detection capability.
Critical asset downtime risk vs FMEA RPN — what's the relationship? This is RPN applied to asset downtime: severity x occurrence x detection, where 'detection' here is framed as control weakness. The structure is identical, so FMEA scoring discipline carries straight over.

Last reviewed 2026-05-12.