ashfordeOU Nonconformance Control (manufacturing-quality/as9100/nonconformance-control)
Use when the task is dispositioning nonconforming aerospace product under AS9100 clause 10.2: identification, segregation, disposition through the material review board, and re-verification after rework.
Domain quick reference
- AS9100 clause 10.2 requires controlling nonconforming output (paraphrase): the part is identified as nonconforming and segregated so it cannot be used or delivered.
- Disposition options: rework (return to the original specification), repair (restore function without full original conformance), scrap, use-as-is (derogation, usually customer approved), and return to supplier.
- The material review board (MRB) holds the disposition authority; repair and use-as-is need MRB approval, rework and scrap do not.
- Reworked output is re-verified against the original acceptance criteria before release; re-verification is mandatory for critical characteristics.
- Safety-critical nonconformances are the strictest case: anything that cannot be reworked to spec is scrapped; repair and use-as-is are not acceptable dispositions for them.
- The disposition record covers identification, segregation, disposition, disposition authority, and customer notification; a record missing any of the five is incomplete.
Workflow
- Identify the nonconforming output and record the nonconformance type (dimensional, material, process, or finish).
- Segregate the part so it cannot be used, shipped, or reworked accidentally.
- Decide the disposition with scripts/nonconformance_logic.py: disposition_decision() walks the safety and rework/repair rules.
- Route repair and use-as-is dispositions through the material review board (MRB) for approval (mrb_approval_required()).
- After rework, re-verify the reworked characteristics (rework_requires_reverification()).
- Close the record only when identification, segregation, disposition, disposition authority, and customer notification are all recorded (disposition_record_complete()).
Pitfalls
- Safety-critical parts: never dispose to repair or use-as-is; only rework that restores the original specification, or scrap. disposition_decision() enforces this rule order.
- Rework re-verification: reworked critical characteristics must be re-verified against the original acceptance criteria before release; skipping re-verification ships an unverified part.
- MRB authority boundaries: repair and use-as-is require MRB approval; rework, scrap, and return to supplier do not. Approving the wrong disposition class breaks the authority chain.
- Record completeness: a disposition record missing identification, segregation, disposition, disposition authority, or customer notification is incomplete regardless of the disposition chosen.
- Repair vs rework definitions: rework restores full conformance to the original specification; repair restores function only. Calling repair "rework" skips the MRB and re-verification steps.
- Derogation discipline: use-as-is (derogation) is a waiver that normally needs customer approval; treating it as a routine disposition bypasses the approval chain.
Behavior contract (gate 3)
The disposition, re-verification, MRB, and record-completeness logic is exercised by the gate 3 contract test: scripts/test_nonconformance_logic.py against scripts/nonconformance_logic.py (stdlib unittest, offline). Run: python3 scripts/test_nonconformance_logic.py
Compliance
- Standards referenced, not reproduced: AS9100 text is proprietary (IAQG/SAE); this skill uses name and paraphrase only. The purchase link is recorded in standards-map.yaml (as9100 entry).
- compliance: STANDARDS-REF, gated: false; the standard is listed reference-only.