Asset Criticality Calculator

Illustrative 5 × 5 ranking, using the greater consequence score.

This selection changes review context only. Formulas and example inputs stay unchanged. Check the model assumptions and applicability for the actual process.

Identify the actual asset, process, work boundary, source documents, units and assumptions. Confirm that the selected model or template applies before using its results.

1 Inputs

2 Results

Criticality score
12 / 25
Likelihood
3 / 5
Consequence
4 / 5
Risk band
High
R = L × max(S, O)
Illustrative 5 × 5 ranking, using the greater consequence score. Scores require a site-approved rubric. A low product cannot waive a safety requirement; review severe consequences separately and document evidence for each score.

Worked example

Example values are illustrative. Replace them with your measured data.

InputValue
Failure likelihood3
Safety / environment consequence4
Operational / cost consequence3

Criticality score: 12 / 25

Related tools

About this calculator

How it works

You rate failure likelihood, safety/environment consequence and operational/cost consequence, each from 1 to 5. The tool takes the worse consequence and multiplies: score = likelihood × max(safety, operational). The score runs from 1 to 25.

Worked example (illustrative inputs)

Likelihood 3, safety 4, operational 3: consequence = max(4, 3) = 4, so score = 3 × 4 = 12.

How to read the result

Bands: 16 or more Critical (RCM or condition-based maintenance plus redundancy and spares), 10–15 High (preventive plus condition monitoring and defined spares), 5–9 Medium (time-based preventive), below 5 Low (run-to-failure acceptable). A score of 12 is High. Because the worse consequence is used, a safety-critical asset cannot be scored down by low production impact.

When to use it

Use it when building or reviewing an asset register, to decide which assets get condition monitoring and held spares and which can run to failure. Score each asset with the same team and scale so rankings are comparable.

À propos de ce calculateur

Traduction (brouillon) — à relire.

Fonctionnement

Vous notez la probabilité de défaillance, la conséquence sécurité/environnement et la conséquence opérationnelle/coût, chacune de 1 à 5. L'outil retient la pire conséquence et multiplie : score = probabilité × max(sécurité, opérationnel). Le score va de 1 à 25.

Exemple chiffré (valeurs d'illustration)

Probabilité 3, sécurité 4, opérationnel 3 : conséquence = max(4, 3) = 4, donc score = 3 × 4 = 12.

Lire le résultat

Paliers : 16 ou plus Critique (RCM ou maintenance conditionnelle, redondance et pièces de rechange), 10–15 Élevé (préventif plus surveillance d'état et rechanges définies), 5–9 Moyen (préventif systématique), moins de 5 Faible (fonctionnement jusqu'à la panne acceptable). Un score de 12 est Élevé. Comme la pire conséquence est retenue, un faible impact sur la production ne peut pas abaisser la note d'un équipement critique pour la sécurité.

Quand l'utiliser

Utilisez-le pour construire ou revoir un registre d'équipements, afin de décider lesquels reçoivent une surveillance d'état et des rechanges en stock, et lesquels peuvent fonctionner jusqu'à la panne. Notez tous les équipements avec la même équipe et la même échelle.

حول هذه الحاسبة

ترجمة (مسودة) — للمراجعة.

طريقة الحساب

تقيّم احتمال العطل وعاقبته على السلامة/البيئة وعاقبته التشغيلية/المالية، كلًّا من 1 إلى 5. تأخذ الأداة العاقبة الأسوأ وتضرب: الدرجة = الاحتمال × max(السلامة، التشغيل). تتراوح الدرجة من 1 إلى 25.

مثال محسوب (قيم توضيحية)

احتمال 3 وسلامة 4 وتشغيل 3: العاقبة = max(4، 3) = 4، إذن الدرجة = 3 × 4 = 12.

قراءة النتيجة

الشرائح: 16 فأكثر حرجة (صيانة RCM أو حسب الحالة مع تكرار وقطع غيار)، و10–15 عالية (وقائية مع مراقبة الحالة وقطع غيار محددة)، و5–9 متوسطة (وقائية دورية)، وأقل من 5 منخفضة (التشغيل حتى العطل مقبول). الدرجة 12 عالية. ولأن العاقبة الأسوأ هي المعتمدة، لا يمكن لتأثير إنتاجي منخفض أن يخفض درجة أصل حرج للسلامة.

متى تستخدمه

استخدمها عند إعداد سجل الأصول أو مراجعته لتحديد الأصول التي تستحق مراقبة الحالة وقطع غيار مخزّنة، وتلك التي يمكن تشغيلها حتى العطل. قيّم كل الأصول بالفريق نفسه والمقياس نفسه.

In one line

Illustrative 5 × 5 ranking, using the greater consequence score. Scores require a site-approved rubric. A low product cannot waive a safety requirement; review severe consequences separately and document evidence for each score.

Worked example

EXAMPLE

Illustrative values (the calculator defaults), not data from a real site.

Inputs
Failure likelihood3 — Possible
Safety / environment consequence4 — Major
Operational / cost consequence3 — Moderate
Results
Criticality score12 / 25
Likelihood3 / 5
Consequence4 / 5
Risk bandHigh
% of asset base~15–20%

Frequently asked questions

How do I decide between the safety and operational consequence ratings?

Score each independently based on the worst realistic outcome of a failure — safety/environment covers injury, environmental release or regulatory exposure, while operational/cost covers production loss, quality impact and repair cost. The calculator automatically uses whichever of the two is higher, so you don't need to combine them yourself.

What if I'm not sure how to rate likelihood?

Base it on failure history if you have it (MTBF/MTTF data, work order frequency), or on engineering judgement and OEM guidance if you don't. It's fine to start with a rough estimate and refine it as you collect more failure data over time.

How many assets should end up in the Critical band?

There's no fixed target, but in most asset bases only a small minority of equipment is genuinely Critical or High — if the majority of your assets score that high, the rating scale is probably being applied too generously and needs recalibrating.

How often should criticality be reassessed?

Re-score after major failures, process or product changes, or capacity expansions, and periodically (for example annually) as part of a broader reliability review — criticality isn't static, it shifts as equipment ages, redundancy changes, or the business becomes more or less dependent on a given asset.

Does a Low score mean I should ignore the asset?

It means run-to-failure is an acceptable, deliberate strategy for that asset — not that it's ignored. You're simply choosing not to invest scarce reliability-engineering effort, spares and monitoring on it, freeing that capacity for the assets whose failure would actually hurt.

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