DPMO and sigma level let processes of different complexity be compared, but only if opportunities are counted
honestly and the shift convention is stated. scripts/dpmo.py computes every defect metric, converts between
DPMO, yield and sigma, and exposes the hidden factory with rolled throughput yield.
Trigger Conditions
Activate this skill when the user:
- Needs DPU, DPMO or a sigma level for a DMAIC baseline or result
- Wants to convert between yield, DPMO, ppm and sigma
- Has a multi-step process and wants RTY or the hidden factory
- Asks how to count defect opportunities, or why ppm and DPMO differ
Workflow
1. DEFINE -> unit, defect, defective, and the fixed list of opportunities per unit (counting-opportunities.md)
2. COUNT -> defects, units, defective units over a representative period
3. COMPUTE -> python scripts/dpmo.py dpmo --defects 38 --units 1200 --opportunities 14
4. PROCESS -> python scripts/dpmo.py rty --steps steps.csv (first-pass yield per step)
5. REPORT -> DPMO and sigma with the opportunity count and the shift convention statedExamples
DPMO = 2,262
Sigma level = 4.34 (short-term, 1.5 shift)Rolled throughput yield = 89.86% (probability a unit passes every step first time)
Hidden factory: 10.1% of units are scrapped or reworked somewhere; worst step: step 2 (95.00%)Sigma table, the 1.5 shift, sigma vs Cpk, and DPU / DPO / DPMO / ppm / FTY / RTY definitions: sigma-conversions.md. Opportunity counting rules, examples, hidden factory and a worked example: counting-opportunities.md.
Output Format
Deliver: the definitions used (unit, defect, opportunities), the computed metrics (DPU, DPMO, yields, sigma with shift convention), RTY by step if relevant, and the interpretation (worst step, gap to target).
Scripts
python scripts/dpmo.py dpmo --defects 38 --units 1200 --opportunities 14 [--defective-units 35]
python scripts/dpmo.py sigma --dpmo 6210 # or --yield 0.9938, or --level 4.5
python scripts/dpmo.py --no-shift sigma --level 3
python scripts/dpmo.py rty --yields 0.98 0.95 0.995 0.97
python scripts/dpmo.py rty --steps steps.csv # step, units_in, defective_units
python scripts/dpmo.py tableExit codes: 0 computed, 2 usage error.
Additional Resources
| File | Content |
|---|---|
| sigma-conversions.md | Sigma/DPMO/yield table, 1.5 shift, metric definitions |
| counting-opportunities.md | Opportunity rules and examples, RTY and hidden factory, worked example |
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Manage and audit an approved supplier list (ASL) / external provider register for ISO 9001 8.4.1, IATF 16949 8.4 and AS9100 8.4.1: supplier status (approved, conditional, probation, pending, disqualified), scope of approval by commodity and process, risk class, certification and expiry, re-evaluation intervals by risk, conditions with end dates, single-source contingency, approver and customer-directed sources. Audits the list for expired or expiring certificates, overdue re-evaluations, conditional or probation status past its decision date, high-risk suppliers without the required certification, single-source suppliers without backup and missing approvers, and checks purchase orders for suppliers that are off-list, disqualified or pending, or buying outside the approved scope. Covers ERP blocks, PO requirements, off-list and emergency purchases.
apqp-phase-planner
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as9100-gap-analyzer
Run an AS9100D / EN 9100:2018 gap analysis for aviation, space and defence suppliers on the requirements added to ISO 9001: on-time delivery and conformity focus, management representative, ethics and human-factors awareness, operational planning and operational risk management, configuration management, product safety, counterfeit-part prevention, special requirements, critical items and key characteristics, external provider register and flow-down, FOD prevention, tooling and NC program control, special process validation, first article inspection (AS9102), traceability, in-service data and nonconforming product control. Generates and scores a worksheet, grades missing core controls as major, and checks invalid n/a claims. Covers AS9101/AS9104, OASIS, AS9102 FAI forms, counterfeit standards (AS5553, AS6174, AS6081), NADCAP and the planned IA9100 transition.
audit-report-writer
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