--- name: fmea description: "A structured failure mode and effects analysis (FMEA) that scores each way a process or product could fail on severity, occurrence, and detection, looks at severity first, and ranks the rest by a risk priority number so the vital-few risks get acted on first. Use when: A process or product change is about to go live, and you want to think through what could go wrong before it does, not after. You have several plausible failure modes and need a defensible way to rank which ones actually deserve attention first. Not for: A failure has already happened and you're investigating why — that's root cause analysis (an A3's 5-Whys), not a forward-looking risk analysis. You're comparing a small set of options against multiple weighted criteria, not ranking failure modes — a weighted decision matrix is the right tool for that." --- # Failure mode and effects analysis (FMEA) A structured failure mode and effects analysis (FMEA) that scores each way a process or product could fail on severity, occurrence, and detection, looks at severity first, and ranks the rest by a risk priority number so the vital-few risks get acted on first. Family: Problem solving / root cause analysis · Format: .xlsx · Domain: core ## What it is A failure mode and effects analysis (FMEA) lists the specific ways a process or product could fail, then scores each one on three dimensions: severity (how bad the effect would be), occurrence (how likely the cause is), and detection (how likely current controls are to catch it before it matters) — each 1 to 10. Severity comes first: a failure mode scored 9 or 10 on severity (someone could get hurt, or a legal or regulatory requirement is broken) needs a recommended action, or a written reason why the current controls are already enough, whatever its other scores. Multiplying the three scores gives a risk priority number (RPN), from 1 to 1,000, and this tool shows it as a secondary ranking for everything else. Be careful with it: very different risks can share the same RPN, and a severe failure that's rare and well detected can score lower than a trivial one that happens often. That's why the 2019 FMEA handbook from the Automotive Industry Action Group (AIAG) and the Verband der Automobilindustrie (VDA), the German automotive industry association, stopped ranking by RPN and replaced it with Action Priority: a lookup table that rates each failure mode high, medium, or low from its severity, occurrence, and detection scores, weighting severity most, then occurrence, then detection. If your customer or industry works to that handbook, use its Action Priority table to decide what to act on. Sources: AIAG & VDA FMEA Handbook, first edition (2019); AIAG Potential FMEA reference manual, fourth edition (2008), which already advised against using an RPN threshold to decide whether action is needed. ## When to use it Use it when: - A process or product change is about to go live, and you want to think through what could go wrong before it does, not after. - You have several plausible failure modes and need a defensible way to rank which ones actually deserve attention first. - You want severity, occurrence, and detection scored explicitly and separately, not blended into one vague 'risk level' that hides which dimension is actually driving the concern. Not when: - A failure has already happened and you're investigating why — that's root cause analysis (an A3's 5-Whys), not a forward-looking risk analysis. - You're comparing a small set of options against multiple weighted criteria, not ranking failure modes — a weighted decision matrix is the right tool for that. - The severity, occurrence, or detection scores would just be guesses with no real basis — an FMEA built on invented scores ranks risks in the wrong order just as confidently as one built on real judgement. ## How to fill it in - **processOrProduct** — What process, product, or system is this analysis covering? - **items** — For each item: what could go wrong, its effect, your severity score, the likely cause, your occurrence score, current controls, and your detection score. The risk priority number is computed from your three scores, never entered directly. - **narrative** — Drafted from the items actually scored: any severity 9 or 10 item first, then the vital-few highest risk priority number items. ## What good looks like The example below analyzes a newly-designed changeover procedure before it goes live — four failure modes scored on severity, occurrence, and detection. It checks severity first (nothing scores 9 or 10, so nothing jumps the queue on severity alone), then names the single highest risk priority number item as the vital-few risk to fix first, not just added to a long list. Full worked example, on-screen and as a downloadable .xlsx: https://www.katafacts.com/katas/fmea ## Common mistakes - **Ranking purely by risk priority number and ignoring a high-severity failure mode because its number is low.** — A failure that could hurt someone but rarely happens can score lower than a nuisance that happens every week. Severity 9 or 10 gets an action, or a written reason the controls are enough, regardless of the number — the same reason the 2019 handbook's Action Priority table weights severity most. - **Setting a risk priority number cut-off, such as "act on anything over 100".** — The number isn't a true measure of risk — the scales aren't evenly spaced and many different score combinations give the same product. A fixed cut-off invites nudging a score down by one to get under the line instead of reducing the risk. - **Scoring severity, occurrence, and detection from a rough overall impression instead of thinking through each dimension separately.** — A failure mode that's severe but well-detected needs a different fix than one that's mild but invisible until it's too late — collapsing the three dimensions into one gut-feel number erases exactly the distinction that makes the risk priority number useful. - **Treating every item on the list as equally worth fixing.** — Same vital-few discipline as every other artifact in this catalogue — a long list of scored risks with no ranking just moves the prioritization problem downstream instead of solving it. - **Writing a recommended action that doesn't actually change severity, occurrence, or detection.** — "Communicate more clearly" or "be more careful" doesn't move any of the three numbers — a real recommended action targets one of them specifically (a physical control, a gate the process can't skip, a check that catches the failure earlier). ## What it connects to Upstream: - **A3 problem solving** (`a3`) — A failure an A3's root cause analysis already traced to a specific cause is exactly the kind of item an FMEA formalizes and ranks alongside other risks in the same process. - **Scoping canvas** (`scoping-canvas`) — A newly-scoped process or procedure change is what an FMEA should analyze before it rolls out, not after something's already gone wrong with it. Downstream: - **Countermeasure matrix** (not in the catalogue yet) — When an FMEA surfaces more recommended actions than can be tackled at once, a countermeasure matrix is where they'd get ranked by impact and effort before committing. ## Where AI helps Judgement — stays with you: - Deciding the real severity, occurrence, and detection scores for each failure mode - Deciding whether a recommended action actually targets the risk it's linked to Analysis — AI helps: - Tightening raw failure-mode, effect, cause, and controls notes into specific, scannable language - Drafting the narrative naming the vital-few highest-risk items - Drafting a recommended action grounded in the notes given, never inventing a fix with no basis in them Drudgery — automated: - Computing the risk priority number from severity, occurrence, and detection, every time a score changes - Ranking items by risk priority number - Exporting to xlsx in the house format --- Failure mode and effects analysis (FMEA) is licensed [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). Attribution: Katafacts (katafacts.com). ## Using this skill Apply this method as part of whatever broader task, instructions, or deliverable you're already working on -- it's a method to use, not a standalone conversation to start. There is no generation tool for this catalogue yet, so draft the artifact's actual content yourself, following the fields above, the same way a person filling this out by hand would. The canonical guide page and a downloadable worked example (.xlsx) are at https://www.katafacts.com/katas/fmea.