GIFSQ Tools · Module 13 — HACCP, Food Safety & Regulatory Compliance · Tool 247 of 500
Rank a food safety risk with the FMEA risk priority number: severity × likelihood × detectability (1–5 each), on the 1–125 scale.
Try sample values — fills the form with the worked example below.
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Risk priority number (1–125)
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Risk band
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Maximum RPN
Equation: Risk priority number (RPN) = severity × likelihood × detectability, each scored 1–5, giving a 1–125 scale. Bands: 1–24 Low, 25–49 Medium, 50–99 High, 100–125 Critical.
Method: Failure mode and effects analysis (FMEA) per IEC 60812:2018, applied to food safety hazards as the risk-ranking method behind the hazard analysis in Codex CAC/RCP 1-1969 (Rev. 2020) and the risk-based thinking in ISO 22000:2018 clause 6.1.
Assumptions: the three scores are the team’s judged ratings for this hazard in this process; detectability 5 means the failure is almost impossible to detect before the product reaches the customer.
Limitations: the RPN ranks hazards for action — it is not a probability, and a low RPN never excuses a missing control for a severe hazard. Re-score when the process or controls change.
Rounding: the RPN is a whole number; no rounding applies.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Method: Failure mode and effects analysis (FMEA) per IEC 60812:2018, applied to food safety hazards as the risk-ranking method behind the hazard analysis in Codex CAC/RCP 1-1969 (Rev. 2020) and the risk-based thinking in ISO 22000:2018 clause 6.1.
Assumptions: the three scores are the team’s judged ratings for this hazard in this process; detectability 5 means the failure is almost impossible to detect before the product reaches the customer.
Limitations: the RPN ranks hazards for action — it is not a probability, and a low RPN never excuses a missing control for a severe hazard. Re-score when the process or controls change.
Rounding: the RPN is a whole number; no rounding applies.
This is a calculation aid, not a laboratory report — confirm against your accredited method before citing a value.
Worked example: Severity 4, likelihood 3, detectability 2: RPN = 4 × 3 × 2 = 24 (Low) on the 1–125 scale.
Enter values above to see results.
Use this matrix to rank hazards for action; Tool 242 (Hazard Analysis Matrix) is the simpler two-factor version with a residual-risk step. Tool 247 of 500 — GIFSQ
