Nuclear & Critical Infrastructure Manufacturing worked example

Spare Part Obsolescence Risk with component criticality score of 20 score: a worked example

Push component criticality score up to 20 score and the picture changes. This example computes every intermediate figure at that operating point. Use it when ranking spare parts for obsolescence action and you need a defensible risk score that combines component criticality, supply availability, and lead-time exposure.

The inputs for this scenario

  • Component criticality score: 20 score (raised for this scenario; the documented default is 8)
  • Supply availability risk score: 6 score (unchanged)
  • Lead-time and stocking exposure score: 5 score (unchanged)

Working through the calculation

  • Applying the documented formula (Obsolescence risk score = component criticality score × supply availability risk score × lead-time and stocking exposure score) to the inputs above produces each figure below.
  • At this operating point the engine returns 11.35 score for obsolescence risk score, the number this scenario is built around.
  • At this operating point the engine returns 20 score for component criticality score.
  • At this operating point the engine returns 6 score for supply availability risk score.
  • At this operating point the engine returns 5 score for lead-time and stocking exposure score.

How this compares with the baseline

  • Against the tool's baseline example, where component criticality score sits at 8 score and the headline result is 6.55 score, this scenario comes in 73.28% above the baseline at 11.35 score.
  • It multiplies component criticality, supply availability risk, and lead-time and stocking exposure into one obsolescence risk priority score for ranking spares. The value of this scenario is the size of the gap it exposes: that gap, priced out over a year, is the budget you can justify spending to close it.

Results at a glance

  • Obsolescence risk score: 11.35 score (headline result)
  • Component criticality score: 20 score
  • Supply availability risk score: 6 score
  • Lead-time and stocking exposure score: 5 score

Run it with your numbers

  • Every input above is editable in the live Spare Part Obsolescence Risk calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.