Six complete FMEA worksheets — one from each major industry — with Severity, Occurrence, and Detection scores, RPN calculations, and recommended actions. Use these as references when building your own FMEA or explaining the method to your team.

Jump to an example:

  1. Manufacturing — Injection Molding (PFMEA)
  2. Automotive — Brake System Assembly (PFMEA)
  3. Healthcare — Surgical Site Infection Prevention (PFMEA)
  4. Software — User Authentication Service (SFMEA)
  5. Food Processing — Pasteurization Line (PFMEA)
  6. Aerospace — Landing Gear Actuator (DFMEA)

Each example uses the standard AIAG-VDA scoring format: RPN = Severity (S) × Occurrence (O) × Detection (D), each rated 1–10. Items highlighted in red have RPN ≥ 100 or Severity ≥ 9 and require immediate corrective action. For a full explanation of the rating scales and the 7-step process, see the complete FMEA guide.

1 Manufacturing — Injection Molding (PFMEA)

Manufacturing

Scope: Process FMEA for a polypropylene bracket injection molding cell. The team analyzed four process steps: material preparation, mold filling, cooling, and ejection. Five failure modes were identified across these steps.

Process StepFailure ModeEffect SCauseOControlsDRPN
Material prepWet pellets (moisture > 0.02%)Splay defects; weakened part; scrap 7Dryer malfunction; wrong drying time3Moisture meter check before run5 105
Mold fillingShort shot (incomplete fill)Defective part — scrap; production delay 7Insufficient injection pressure4Visual inspection 1/shift4 112
Mold fillingFlash at parting lineDimensional non-conformance; assembly failure 5Excessive clamp pressure; worn tooling3CMM check 2/shift3 45
CoolingWarpage (> 0.5 mm flatness)Assembly failure; customer complaint 6Uneven cooling; blocked water line5CMM flatness check 1/hour3 90
EjectionPart sticking to moldPart damage; production stoppage 6Insufficient draft angle; worn ejector pins3Operator visual each cycle4 72
Actions taken: Short shot (RPN 112) → in-cavity pressure sensor added, alarm set at threshold. Wet pellets (RPN 105) → dryer temperature alarm installed, moisture log required per lot. Warpage (RPN 90) → cooling channel flush schedule added weekly.

2 Automotive — Brake System Assembly (PFMEA)

Automotive

Scope: Process FMEA for a disc brake caliper assembly line at a Tier 1 automotive supplier. Required as part of IATF 16949 APQP documentation. Note how items with S = 9 require action even when RPN appears low.

Process StepFailure ModeEffect SCauseOControlsDRPN
Banjo bolt assemblyBrake fluid leak at fittingReduced braking; potential accident 9Under-torqued fitting; operator skips torque wrench2Torque wrench click audit, 100% check2 36
Piston installationPiston installed reversedBrake drag; uneven wear; vehicle pull 7No poka-yoke; operator error3Visual check by line supervisor4 84
Dust boot seatingDust boot not fully seatedCorrosion ingress; premature wear; field return 6Manual press operation; insufficient force4Go/no-go gauge check, 1 per hour3 72
Brake pad installationWrong friction material grade installedInadequate braking performance; noise; safety concern 9Look-alike part numbers; kitting error2Barcode scan at point of use2 36
Leak testLeak test pressure set too low (pass bad parts)Defective calipers escape to vehicle assembly 8Gauge drift; calibration lapse2Calibration log, annual schedule4 64
Key insight: Both S = 9 items (brake fluid leak and wrong pad grade) have RPN of only 36 — but both received immediate action because Severity ≥ 9 always overrides RPN rank. Actions: electronic torque tool with interlock on banjo bolt station; RFID part verification replacing barcode scan. Calibration interval for leak test gauge shortened from annual to quarterly.

3 Healthcare — Surgical Site Infection Prevention (PFMEA)

Healthcare

Scope: Process FMEA for the surgical site preparation and sterile field maintenance process in an orthopedic operating room. Developed as part of a Joint Commission quality improvement initiative. Healthcare FMEA often uses the same RPN structure but adds a criticality review for any S ≥ 8.

Process StepFailure ModeEffect SCauseOControlsDRPN
Skin antisepsisInadequate prep coverage (area too small)Surgical site infection (SSI); extended hospital stay 8No standard boundary marked; surgeon variation4Verbal confirmation by scrub tech5 160
Skin antisepsisAntiseptic solution applied before dryingChemical burn; reduced antiseptic efficacy; SSI risk 7Time pressure; no timer used4Policy checklist in OR4 112
Sterile drapingSterile drape contaminated during placementBreak in sterile field; SSI risk; procedure may be halted 8Drape contacts non-sterile surface; inadequate team spacing3Circulator monitors sterile field3 72
Instrument handlingNon-sterile instrument passed onto sterile fieldSterile field breach; potential infection 9Distraction; look-alike sterile/non-sterile packaging2Two-nurse sterile confirmation2 36
Wound closureRetained surgical spongeRe-operation; patient harm; malpractice claim 10Manual count error; distraction; emergent cases2Manual count before/after; X-ray on count discrepancy3 60
Actions taken: Skin prep coverage (RPN 160) → standardized prep boundary template introduced for each procedure type. Antiseptic drying (RPN 112) → mandatory 3-minute timer added to surgical checklist. Retained sponge (S=10, RPN 60) → radio-frequency (RF) sponge detection system implemented on all elective cases regardless of low O score.

4 Software — User Authentication Service (SFMEA)

Software

Scope: System FMEA for a B2B SaaS authentication service handling OAuth 2.0 login, session management, and password reset flows. Conducted as part of a pre-launch security and reliability review. Software FMEA follows the same RPN logic; Severity 9–10 items typically involve data breaches or compliance violations.

Function / ServiceFailure ModeEffect SCauseOControlsDRPN
OAuth loginAuthorization code reuse (replay attack)Unauthorized account access; data breach 9Code not invalidated after first use2Code TTL set to 60s; no reuse check5 90
Session managementSession token not invalidated on logoutSession hijacking; unauthorized access after logout 8Stateless JWT; no server-side revocation list4Token expiry set to 24h; no revocation6 192
Password resetPassword reset link valid for > 24 hoursAccount takeover if email is compromised 8No TTL enforcement on reset tokens3Manual security review quarterly6 144
Login endpointNo rate limiting — brute force possiblePassword enumeration; account compromise 8Rate limiter not applied to /auth/login3WAF in front of service4 96
Error handlingStack trace returned in 500 responseInternal paths and library versions exposed; recon aid for attacker 6Debug mode enabled; no error sanitization4None — not currently checked8 192
Actions taken: Session revocation (RPN 192) → Redis-based token blacklist added; logout now invalidates server-side. Stack trace exposure (RPN 192) → global error handler implemented returning generic 500 message; debug flag forced off in production CI pipeline. Password reset TTL (RPN 144) → 1-hour expiry enforced with one-time-use invalidation on click.

5 Food Processing — Pasteurization Line (PFMEA)

Food Processing

Scope: Process FMEA for an HTST (High-Temperature Short-Time) pasteurization line at a dairy plant. HACCP (Hazard Analysis Critical Control Points) is the food industry’s equivalent of FMEA; here the same RPN structure is applied to the pasteurization critical control point. FDA 21 CFR Part 110 compliance is in scope.

Process StepFailure ModeEffect SCauseOControlsDRPN
Pasteurization / Heat treatmentProduct temperature below 72°C (161.6°F)Surviving pathogens (Listeria, Salmonella); consumer illness; recall 10Heat exchanger fouling; flow rate too high2Continuous temp recorder; flow diversion valve (FDV)1 20
Flow diversion valveFDV fails to divert (stuck open)Under-processed product reaches filler; pathogen risk 10Valve actuator failure; pneumatic fault2FDV position sensor; daily function test2 40
CIP (clean-in-place)CIP cycle terminated earlyResidual biofilm; microbial contamination of next batch 9Operator manual override; timer fault2CIP log review; ATP swab test after cycle3 54
Holding tubeHolding time < 15 secondsInsufficient pasteurization; pathogen survival 10Flow rate exceeds design maximum2Flow meter interlock; FDV triggers if flow too high1 20
Filler/packagingPost-pasteurization recontaminationPathogen in final product; short shelf life; recall 9Filler not sanitized; aseptic barrier breach2Pre-run sanitation check; environmental swabbing4 72
Key insight: All four S = 9–10 items have low RPN because existing controls (FDV, continuous temperature recording, flow interlocks) are highly effective. This is correct FMEA behavior — strong detection controls lower D and thus lower RPN, but the S = 10 items remain Critical Control Points (CCPs) in the HACCP plan and cannot be deprioritized.

6 Aerospace — Landing Gear Actuator (DFMEA)

Aerospace

Scope: Design FMEA for a hydraulic actuator in a commercial aircraft main landing gear system. Performed per SAE ARP4761 guidelines. In aerospace, Severity = 10 items are treated as “catastrophic” and must achieve a target probability of < 10−9 per flight hour through redundancy and design changes, regardless of current RPN.

Function / ComponentFailure ModeEffect SCauseOControlsDRPN
Actuator / Extend gear on commandActuator fails to extend (gear up on landing)Gear-up landing; hull loss; fatalities 10Hydraulic seal failure; blocked port1Redundant hydraulic circuit; manual extension backup; pre-flight check1 10
Actuator / Retract gear after takeoffActuator extends uncommanded in flightIncreased drag; structural overload above Vlo 9Control valve stiction; electronic fault1Dual-channel control valve; BITE monitoring2 18
Actuator body / Contain hydraulic pressureExternal hydraulic leak (actuator body crack)Hydraulic fluid fire risk; loss of primary hydraulics 9Material fatigue; stress concentration at port boss2FEA stress analysis; NDT inspection on prototypes3 54
Position sensor / Report gear stateFalse “gear down and locked” indicationCrew believes gear down; no precautionary action before landing 10Sensor wiring short; connector corrosion2Dual independent sensors; disagree logic in FCC2 40
Locking mechanism / Lock gear downOver-centre lock does not engageGear collapses on landing; hull damage; injuries 10Wear on lock link; debris in mechanism1Mechanical design safety factor; functional test every 500 cycles2 20
Key insight: Low RPNs across all items reflect the multiple layers of redundancy built into aerospace design. However, every S = 9–10 item is subject to SAE ARP4761 safety analysis to demonstrate target failure probability regardless of RPN. The DFMEA here feeds directly into the Fault Tree Analysis (FTA) and Common Cause Analysis (CCA) required for FAA/EASA type certification.

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7Quick Reference: RPN Risk Levels

These thresholds are guidelines — set your own based on industry and risk tolerance. Always act on S ≥ 9 regardless of RPN.

8Related Resources