Failure Analysis Report

Structures an engineering failure investigation into a defensible, court-ready failure analysis report. Covers every element from investigation scope and scene methodology through root cause determination and expert opinion, producing a DRAFT for licensed PE stamp and signature before delivery.

Before You Start

This skill produces DRAFT documentation only. All content requires review, signature, and professional engineer stamp by a licensed PE before delivery to any attorney, insurer, court, or regulatory body.

Critical rule — applicable standards: The skill always uses standards, codes, and editions that were in effect at the time of construction, manufacture, or installation — not current editions. This is a hard requirement. Flag any case where the applicable edition is unknown as [STANDARDS DATE UNKNOWN — PE TO CONFIRM].

Data integrity rule: Never fabricate measurement values, test results, laboratory data, or failure observations. All quantitative findings are entered by the engineer. If a value is unavailable, mark it [DATA NOT AVAILABLE — PE TO PROVIDE].

Flow

Phase 1 — Investigation Identification and Scope

Ask one question at a time. Collect:

1. Case or file number (no personally identifying information for claimants)
2. Investigation date(s) and report preparation date
3. Client name and retention type (insurer / plaintiff counsel / defense counsel / regulatory body / owner)
4. Incident date, location (city/state/type of facility — no street addresses in the body unless the PE specifically provides them)
5. Failure type — select one primary type to set routing in Phase 2:
• A. Structural (building, foundation, retaining wall, floor/ceiling system, roof)
• B. Mechanical (machinery, equipment, piping, vehicle or transportation)
• C. Fire Origin and Cause (building fire, vehicle fire, equipment fire)
• D. Electrical (wiring, panels, transformers, electrical equipment)
• E. Product / Consumer or Industrial Product (manufacturing defect, design defect, failure in service)
6. Brief incident description (as reported by client — label [AS REPORTED — NOT VERIFIED])
7. Scope limitations (areas not accessed, evidence not available, testing not performed)

Phase 2 — Scene Documentation Methodology

Collect the documentation approach used during the investigation:

• Site access: Date(s) of site visit, who accompanied the engineer, any access restrictions
• Documentation method: Photography (still / video / 3D laser scan / drone), sketches, measurements
• Evidence preservation protocol: Any evidence tagged, sampled, or collected for laboratory analysis
• Chain-of-custody status: Evidence retained by PE / returned to owner / transferred to lab — flag any gaps as [CHAIN OF CUSTODY GAP — DOCUMENT]
• Destructive testing notice: If any destructive examination was performed, document that all parties were notified or waived notice

Phase 3 — Physical Evidence Inventory

For each piece of physical evidence or observed condition, collect:

Flag any evidence that was altered, missing, or unavailable as [EVIDENCE CONDITION FLAG — DOCUMENT IN LIMITATIONS].

Phase 4 — Applicable Standards and Codes

Collect or confirm the standards in effect at the time of construction, manufacture, or installation:

Rule: If the applicable edition cannot be confirmed, mark it [STANDARDS DATE UNKNOWN — PE TO CONFIRM]. Never substitute a current edition for an unknown historical edition without explicit PE direction.

Add a note if current standards are referenced for comparison only: [CURRENT EDITION — FOR COMPARISON ONLY; NOT THE APPLICABLE STANDARD].

Phase 5 — Failure Mode Hypothesis Screening

Generate 2–5 failure mode hypotheses based on the investigation findings. For each hypothesis:

Route by failure type for domain-specific hypothesis framing:

A. Structural: Consider overload, material defect, design deficiency, construction defect, maintenance neglect, environmental deterioration, improper modification.

B. Mechanical: Consider fatigue fracture, overload, corrosion/erosion, improper assembly, maintenance neglect, material defect, design deficiency, misuse or abuse.

C. Fire: Apply NFPA 921 scientific method. Consider accidental (electrical, mechanical, chemical, open flame, smoking) vs. incendiary vs. natural (lightning). Each hypothesis must be evaluated by physical evidence — never assume incendiary without positive evidence.

D. Electrical: Consider overcurrent, insulation breakdown, arcing (series / parallel), connection failure, overvoltage, ground fault, equipment malfunction, improper installation.

E. Product: Consider manufacturing defect, design defect, failure to warn, misuse, post-sale modification, end-of-service-life failure.

Phase 6 — Root Cause Determination

Based on Phase 5 screening, state the most probable cause:

Most probable root cause: [State clearly and specifically]

Basis: [List the evidence that supports this determination]

Exclusions: [List hypotheses eliminated and why]

Degree of certainty: Definitive / More probable than not / Indeterminate — explain basis for each.

If certainty is indeterminate, document what additional investigation, testing, or evidence would be needed to reach a conclusion. Label the section [ROOT CAUSE — INDETERMINATE — SEE ADDITIONAL INVESTIGATION NEEDED].

Phase 7 — Expert Opinion

Collect the expert opinion from the PE. Draft using the following structure:

> "Based on my investigation, analysis of the physical evidence, review of applicable standards in effect at the time of [construction/manufacture], and my professional training and experience as a licensed [discipline] engineer, it is my professional opinion that [most probable root cause statement]. This opinion is stated to a [reasonable degree of engineering certainty / more probable than not] standard."

Label the entire opinion section: [DRAFT EXPERT OPINION — PE TO REVIEW, REVISE, AND ADOPT AS THEIR OWN]

The PE must adopt this language in their own words. This draft is a structural aid, not a ready-to-sign opinion.

Phase 8 — Limitations Statement

Include a standard limitations statement:

• Investigation was limited to the areas, evidence, and time described in this report
• Opinions are based on information available at the time of this report
• Additional evidence or testing may modify the conclusions
• This report was prepared in anticipation of litigation and may be subject to work-product protection (if applicable — PE to confirm with retaining counsel)

Add any case-specific limitations identified during the investigation.

Phase 9 — DRAFT Report Assembly

Compile all phases into the following structured report:

FAILURE ANALYSIS REPORT — DRAFT
Case / File No.: [From Phase 1]
Report Date: [Phase 1]
Incident Date: [Phase 1]
Prepared for: [Client name and retention type]
Prepared by: [PE name, discipline, license no. — PE TO COMPLETE]

1. EXECUTIVE SUMMARY
   [2–4 sentences: incident description, investigation scope, most probable root cause]
   DRAFT — FOR PE REVIEW ONLY

2. BACKGROUND AND SCOPE
   [Incident description — AS REPORTED — NOT VERIFIED]
   [Scope and limitations from Phase 1]

3. SCENE DOCUMENTATION METHODOLOGY
   [From Phase 2]

4. PHYSICAL EVIDENCE INVENTORY
   [Table from Phase 3]
   [Chain-of-custody flags]

5. APPLICABLE STANDARDS AND CODES
   [Table from Phase 4]
   [Standards-at-time-of-construction notation]

6. FAILURE MODE HYPOTHESIS SCREENING
   [Table from Phase 5 with routing-specific hypotheses]

7. ROOT CAUSE DETERMINATION
   [From Phase 6]
   [Basis and exclusions]

8. EXPERT OPINION
   [DRAFT text from Phase 7]
   DRAFT EXPERT OPINION — PE TO REVIEW, REVISE, AND ADOPT AS THEIR OWN

9. LIMITATIONS
   [From Phase 8]

APPENDICES
   Appendix A: Photographs (referenced by item number)
   Appendix B: Physical evidence inventory (expanded)
   Appendix C: Documents and records reviewed
   Appendix D: Curriculum vitae of PE

─────────────────────────────────────────
DRAFT — FOR LICENSED PE REVIEW ONLY
This document is not finalized and must not be delivered to any attorney, insurer,
court, or regulatory body until reviewed, revised, and stamped by a licensed
Professional Engineer (PE).

Reviewing PE: _________________________ License No.: _______________ State: ____
Discipline: ___________________________ Stamp: ______________________________
Signature: ____________________________ Date: ________________________________
─────────────────────────────────────────

Present the complete DRAFT and list any open items or flags for PE attention.

Key Rules

• Standards at time of construction is a hard rule. Never apply a current code edition to a historical project without explicit PE direction. Always confirm the applicable edition.
• No fabricated data. All measurements, test results, and observations come from the engineer. If a value is missing, flag it.
• Fire origin investigations must follow NFPA 921. Never state incendiary cause without positive physical evidence. Incendiary is a conclusion of last resort after all accidental hypotheses are eliminated.
• Expert opinion is always DRAFT. The PE must adopt, revise, and sign the opinion in their own professional capacity.
• Chain of custody: Any gap in chain of custody must be documented in the limitations section — it may affect admissibility.
• Work-product privilege: Remind the PE to confirm with retaining counsel whether the report is privileged before it is transmitted.

Output Format

The final output is a single structured DRAFT report (as defined in Phase 9) plus:

• A numbered open-items list of any flags, data gaps, or indeterminate conclusions requiring PE attention
• A note confirming the report is DRAFT and must not be delivered until PE review and stamp

Feedback

If the user expresses an unmet need, a workflow gap, or dissatisfaction with the skill, surface the contribution link:

Open an issue on GitHub