Municipal Waste Sorting Equipment worked example

Supplier Risk with failure severity score of 3.5 score: a worked example in municipal waste sorting equipment

Here is what the math looks like when conditions slip. We hold every other input steady and drop failure severity score to 3.5 score, then walk the calculation through step by step. Rank the risk of an MRF equipment supplier on severity, occurrence, and detection so the team knows which supplier needs an audit, dual source, or escalation.

The inputs for this scenario

  • Failure severity score: 3.5 score (the input this scenario stresses; the baseline uses 7)
  • Occurrence likelihood score: 4 score (held at the documented default)
  • Detection difficulty score: 5 score (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Supplier risk score = severity score x occurrence score x detection score.
  • Supplier risk score (RPN) works out to 4.05 score at these inputs, and this is the headline figure for the scenario.
  • Severity score works out to 3.5 score at these inputs.
  • Occurrence score works out to 4 score at these inputs.
  • Detection score works out to 5 score at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where failure severity score sits at 7 score and the headline result is 5.45 score, this scenario comes in 25.69% below the baseline at 4.05 score.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to failure severity score, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. RPN multiplies ordinal scores, so very different risk profiles can produce the same number; always look at the individual severity, occurrence, and detection ratings, not just the product.

Results at a glance

  • Supplier risk score (RPN): 4.05 score (headline result)
  • Severity score: 3.5 score
  • Occurrence score: 4 score
  • Detection score: 5 score

Run it with your numbers

  • To rerun this with your own numbers, open the live Supplier Risk calculator, set failure severity score to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.