Cleanroom & Contamination Control worked example

Contamination Risk Score with contamination impact severity score of 4 score: a worked example in cleanroom & contamination control

This worked example runs the contamination risk score numbers for a tougher week than the baseline: contamination impact severity score of 4 score instead of the typical 8 score. Score contamination-control risk using impact severity, event likelihood, and weakness of current detection controls.

The inputs for this scenario

  • Contamination impact severity score: 4 score (the input this scenario stresses; the baseline uses 8)
  • Contamination event likelihood score: 5 score (held at the documented default)
  • Detection control weakness score: 4 score (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Contamination Risk Score risk score = contamination impact severity score × contamination event likelihood score × detection control weakness score.
  • Contamination Risk Score risk score works out to 4.35 score at these inputs, and this is the headline figure for the scenario.
  • Contamination impact severity score works out to 4 score at these inputs.
  • Contamination event likelihood score works out to 5 score at these inputs.
  • Detection control weakness score works out to 4 score at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where contamination impact severity score sits at 8 score and the headline result is 5.95 score, this scenario comes in 26.89% below the baseline at 4.35 score.
  • Use it during a contamination-control risk assessment, a deviation review, or when ranking a backlog of remediation actions. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Contamination Risk Score risk score: 4.35 score (headline result)
  • Contamination impact severity score: 4 score
  • Contamination event likelihood score: 5 score
  • Detection control weakness score: 4 score

Run it with your numbers

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

Last reviewed 2026-05-12.