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Belt 2 of 4 · Team member

Yellow Belt

Support Green Belt projects with process thinking, basic problem-solving tools, data collection, and structured waste walks — contribute without owning the full DMAIC charter.

What this belt means

Role & typical depth

Yellow Belt is the capable team member. You help scope problems, map processes, collect data, run 5 Whys and fishbones, and join waste walks. A Green Belt (or Black Belt coach) usually owns the project charter and statistical decisions.

Typical depth: solid tool literacy and facilitation support — not full MSA, DOE, or hypothesis testing. You should leave Yellow able to fill a SIPOC, sketch a process map, and turn a “we think” into a checkable cause list.

Austin / Toyota training angle: Yellow Belts strengthen stand-up problem solving and give trainers a bench of people who can document work and spot muda systematically.

Learning goals

  • Gather Voice of the Customer (VOC) inputs and translate them into rough Critical-to-Quality (CTQ) statements.
  • Build a complete SIPOC (Suppliers, Inputs, Process, Outputs, Customers).
  • Draw a basic process map (flow chart) of a real work sequence.
  • Facilitate 5 Whys and a fishbone (Ishikawa) with a small team.
  • Run a structured waste walk and log findings against the 8 wastes.
  • Use check sheets / simple tallies; explain mean, range, and why sample size matters (awareness).
  • Recognize pull/kanban and poka-yoke ideas on the floor.

Core Lean topics (Yellow depth)

Gemba & waste walks

Go to the real place with a purpose. Observe, ask why, record wastes with evidence — not blame. Close the loop: who owns each finding?

Process observation

Separate what the document says from what people actually do. Note cycle time, waits, rework loops, and handoffs.

Basic standard work

Document the current best method: sequence, timing, key points, reasons. Yellow Belt contributes observations; Green Belt often owns the standard.

Poka-yoke awareness

Error-proofing devices and process designs. Ask: can we make the wrong action impossible or immediately obvious?

Pull / kanban awareness

Produce or move material only when the downstream signal says so. Spot push vs. pull on your line.

Andon in practice

Know how to call for help, what escalation looks like, and why stopping briefly beats shipping defects.

Core Six Sigma / DMAIC (Yellow depth)

VOC basics

Collect customer (or next-process) needs via interviews, complaints, specs, and observation. Sort into must-be vs. delight factors; draft CTQs that are measurable.

SIPOC

One-page project framing tool used in Define. Keeps scope honest: who supplies what, what the process is (high level), what leaves, who receives it.

Process maps intro

Swimlanes or simple flowcharts: start/end, decisions, delays, rework. Yellow Belt maps “as-is”; Green Belt may add data boxes and VSM later.

Fishbone (Ishikawa)

Cause categories (often 6M: Man, Machine, Method, Material, Measurement, Mother Nature). Brainstorm, then verify — don’t treat the board as proof.

5 Whys

Drill from symptom to system cause. Stop when a countermeasure is actionable; watch for jumping to blame or stopping too early.

Basic stats awareness

Know: population vs. sample, average vs. variation, that charts beat tables for spotting trends. You collect data; Green Belt selects tests and control charts.

Key tools & glossary

SIPOC
High-level process framing for Define-phase alignment.
CTQ
Critical to Quality — measurable characteristic tied to VOC.
Check sheet
Structured tally form for defect types, times, locations.
Pareto
Vital few vs. useful many — 80/20 awareness for prioritizing causes.
Operational definition
Clear rule for how a metric is measured so two people get the same result.
Kanban
Signal that authorizes production or withdrawal in a pull system.
Takt time
Available time ÷ customer demand — pace the process should meet (awareness).
Heijunka
Leveling production volume/mix — awareness only at Yellow.

Curated external resources

ASQ — SIPOC Diagram

Define-phase framing tool every project team should share.

ASQ — Fishbone Diagram

Cause-and-effect structure for team brainstorms.

ASQ — Pareto Chart

Vital-few prioritization with Pareto thinking.

ASQ — Check Sheet

Structured data collection for defect tallies.

ASQ — DMAIC

Phase-by-phase tool map for DMAIC projects.

ASQ — Voice of the Customer

VOC methods that feed CTQs.

ASQ — Certified Six Sigma Yellow Belt

BoK orientation for Yellow Belt depth.

IASSC — Yellow Belt certification

Exam-based Yellow Belt competency framing.

NIST MEP — Lean and Process Improvement

U.S. MEP lean services: VSM, 5S, changeover, continuous improvement for manufacturers.

NIST MEP — Training Within Industry (TWI)

Government primer on TWI and Job Instruction for manufacturers.

LEI — Training Within Industry (TWI)

Lexicon primer on TWI J-programs and Job Instruction four steps.

LEI — Standardized Work

Standardized work as the baseline for kaizen.

EPA — Lean in Government Starter Kit (PDF)

Practical Lean event / facilitator-oriented public kit.

EPA — Lean methods: Kaizen

Kaizen event framing from EPA Lean toolkit.

MIT OCW — Introduction to Lean Six Sigma Methods

Free university course materials covering Lean and Six Sigma methods.

MIT OCW — Six Sigma Basics PDF

DMAIC and variation primer slides from MIT OCW.

LEI — TPS or the Toyota Way?

Connects TPS house tools to Toyota Way people system.

CSSC — Free Six Sigma training manuals

Free self-study manuals by belt (some fetchers see 403; page is the known free-manual hub).

Study path (checklist)

  1. Complete White Belt goals if you haven’t — shared vocabulary first.
  2. Build a SIPOC for a real process you know (training flow, changeover, inspection).
  3. Map the same process as-is; mark waits, rework, and handoffs.
  4. Run one 5 Whys and one fishbone with a peer; verify one cause with a check sheet.
  5. Lead or co-lead a 30–60 min waste walk; log 8-waste tags and owners.
  6. Draft VOC → CTQ for one customer or next process; define how you’d measure it.
  7. When ready for project ownership, continue to Green Belt.

Your notes / Q&A

Empty — paste chat excerpts, SIPOC drafts, or waste-walk photos notes later.
Empty card — reserved for Factory Training Bot growth.