Inspection Deficiency Severity Score Calculator
Calculate a composite severity score for inspection deficiencies using a weighted risk-priority model based on defect severity, occurrence frequency, detectability, and regulatory/safety impact.
1 = Negligible | 5 = Moderate | 10 = Catastrophic / Safety-Critical
1 = Extremely Rare | 5 = Occasional | 10 = Almost Certain
1 = Almost Certain Detection | 5 = Moderate | 10 = Virtually Undetectable
1 = No Regulatory Impact | 2 = Minor Concern | 3 = Major Violation
0 = First Occurrence | 1 = Previously Noted | 2 = Repeat / Chronic
Formula
Step 1 — Base Risk Priority Number (RPN):
RPN = S × O × D
Step 2 — Adjusted Deficiency Severity Score (DSSraw):
DSSraw = (S × O × D × R) + (P × 10)
Step 3 — Normalized DSS (0–100 scale):
DSSnorm = (DSSraw / 3,020) × 100
Where:
- S = Defect Severity Level (1–10)
- O = Occurrence / Frequency Rating (1–10)
- D = Detection Difficulty Rating (1–10; higher = harder to detect)
- R = Regulatory / Compliance Impact Weight (1–3)
- P = Repeat / Recurrence Penalty (0–2)
- 3,020 = Maximum possible raw score [(10×10×10×3) + (2×10)]
- P × 10 = Penalty points added for repeat deficiencies (0, 10, or 20)
Classification Thresholds (Normalized DSS):
- 0–19.9 → Low
- 20–39.9 → Moderate
- 40–59.9 → High
- 60–79.9 → Critical
- 80–100 → Severe / Stop-Work
Assumptions & References
- The base RPN model is derived from FMEA (Failure Mode and Effects Analysis) methodology as defined in AIAG & VDA FMEA Handbook (2019) and MIL-STD-1629A.
- The Regulatory Impact Weight (R) extends the standard RPN to account for compliance consequences, consistent with ISO 9001:2015 §10.2 (nonconformity and corrective action) and ISO 45001:2018 risk frameworks.
- The Recurrence Penalty (P × 10) reflects industry practice in Joint Commission and FDA 21 CFR Part 820 quality system regulations, which treat repeat deficiencies as elevated risk indicators.
- Detection ratings follow the AIAG FMEA scale where 1 = near-certain detection and 10 = virtually undetectable.
- Severity ratings follow the AIAG/VDA scale: 1–2 = negligible, 3–4 = minor, 5–6 = moderate, 7–8 = major, 9–10 = catastrophic/safety-critical.
- Occurrence ratings follow the AIAG/VDA scale: 1–2 = rare (<1 in 1,000,000), 9–10 = almost certain (>1 in 2).
- Normalization to a 0–100 scale is applied to facilitate cross-deficiency comparison and reporting dashboards.
- Classification thresholds and corrective action timelines are illustrative; organizations should calibrate these to their specific regulatory environment, industry standards, and internal risk tolerance.
- This calculator does not replace a formal FMEA, risk assessment, or regulatory compliance review conducted by qualified professionals.