Rail Signaling & Wayside Equipment worked example

Supplier Risk with component severity if supplier defect reaches track of 15 score: a worked example in rail signaling & wayside equipment

What does the result look like when component severity if supplier defect reaches track reaches 15 score? The full calculation is worked below with real intermediate numbers. Use it when supplier risk in rail signaling and wayside equipment needs a defensible ranking against other rail signaling and wayside equipment risks for the next review.

The inputs for this scenario

  • Component severity if supplier defect reaches track: 15 score (raised for this scenario; the documented default is 6)
  • Likelihood supplier ships a nonconforming part: 4 score (unchanged)
  • Ability to catch supplier defect before install: 3 score (unchanged)

Working through the calculation

  • Applying the documented formula (Supplier risk score = supplier risk severity score × supplier risk occurrence score × supplier risk detection score) to the inputs above produces each figure below.
  • At this operating point the engine returns 8.15 score for supplier risk score, the number this scenario is built around.
  • At this operating point the engine returns 15 score for supplier risk severity score.
  • At this operating point the engine returns 4 score for supplier risk occurrence score.
  • At this operating point the engine returns 3 score for supplier risk detection score.

How this compares with the baseline

  • Against the tool's baseline example, where component severity if supplier defect reaches track sits at 6 score and the headline result is 4.55 score, this scenario comes in 79.12% above the baseline at 8.15 score.
  • A figure at this level is achievable when component severity if supplier defect reaches track is genuinely sustained, not just peaked for a shift. RPN treats 6x4x3 and 3x4x6 as equal even though a high-severity defect that also evades detection is far more dangerous, so always review severity on its own before acting on the score.

Results at a glance

  • Supplier risk score: 8.15 score (headline result)
  • Supplier risk severity score: 15 score
  • Supplier risk occurrence score: 4 score
  • Supplier risk detection score: 3 score

Run it with your numbers

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

Last reviewed 2026-05-12.