Study guide
5.2 Project Planning: WBS, Gantt Charts & Communication Plans
ASQ Certified Six Sigma Yellow Belt CSSYB
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1 Introduction & Exam Overview
About the ASQ CSSYB Exam How to Use This Study Guide
2 Chapter 1: Six Sigma & Lean Fundamentals
1.1 Six Sigma Foundations, Principles & History 1.2 Lean Foundations, Principles & The 8 Wastes 1.3 Six Sigma Roles & Responsibilities
3 Chapter 2: Team Basics & Dynamics
2.1 Team Types & Stages of Team Evolution 2.2 Team Decision-Making & Idea Generation Tools 2.3 Communication Methods & Meeting Management
4 Chapter 3: Quality Tools & Six Sigma Metrics
3.1 The 7 Basic Quality Tools 3.2 Six Sigma Process Performance Metrics & COPQ
5 Chapter 4: Define Phase — Project Identification & Scope
4.1 Voice of the Customer (VOC) & Critical-to-Quality (CTQ) 4.2 Project Selection & Stakeholder Analysis 4.3 Process Definition with SIPOC & Supply Chain Basics
6 Chapter 5: Define Phase — Project Management Basics
5.1 The Project Charter & Problem Statements 5.2 Project Planning: WBS, Gantt Charts & Communication Plans 5.3 Project Management Tools & Tollgate Reviews
7 Chapter 6: Measure Phase — Data Collection & Statistics
6.1 Basic Statistics: Central Tendency & Dispersion 6.2 Data Types & Classification 6.3 Data Collection Plans, Operational Definitions & Sampling 6.4 Data Collection Techniques: Check Sheets, Checklists, Surveys & Interviews
8 Chapter 7: Measure Phase — Measurement System Analysis
7.1 Measurement System Fundamentals: Precision, Accuracy & Bias 7.2 Gauge Repeatability & Reproducibility (GR&R)
9 Chapter 8: Analyze Phase — Process & Root Cause Analysis
8.1 Process Analysis: 5S & Value Analysis 8.2 Failure Mode and Effects Analysis (FMEA) 8.3 Root Cause Analysis: 5 Whys, Process Mapping, 8D, Force-Field & Matrix Charts
10 Chapter 9: Analyze Phase — Corrective Action & Variation
9.1 Corrective & Preventive Action Processes 9.2 Common Cause vs Special Cause Variation 9.3 Basic Distribution Types: Normal, Binomial & Poisson
11 Chapter 10: Analyze Phase — Relationships & Hypothesis Testing
10.1 Correlation & Scatter Plots 10.2 Simple Linear Regression & Prediction 10.3 Hypothesis Testing Concepts: Hypotheses, Errors & P-Values
12 Chapter 11: Improve Phase — Implementation Techniques
11.1 Kaizen & Kaizen Blitz Events 11.2 Plan-Do-Check-Act (PDCA) & Solution Selection 11.3 Cost-Benefit Analysis & Financial Validation
13 Chapter 12: Control Phase — Sustaining Improvements
12.1 Control Plans & Process Monitoring 12.2 Statistical Process Control: X-bar & R Charts 12.3 Document Control, Standard Operating Procedures & Project Hand-off
5.2 Project Planning: WBS, Gantt Charts & Communication Plans
Key Takeaways Explain This Topic AI
The Work Breakdown Structure (WBS) decomposes the entire project scope into hierarchical, deliverable-oriented work packages following the strict 100% Rule.
The 100% Rule mandates that the WBS capture exactly 100% of the project scope and deliverables—including internal project management activities—with zero omissions and zero extraneous work.
Gantt charts provide an intuitive visual timeline of project execution, illustrating task durations, start and finish dates, predecessor dependencies, and milestone checkpoints.
The Critical Path Method (CPM) identifies the longest continuous sequence of dependent activities, which determines the minimum overall project completion time; tasks on this path have zero total float.
A structured Project Communication Plan systematically defines stakeholder information needs, reporting channels, communication frequency, and assigned owners to ensure transparency and sustain executive engagement.
Last updated: September 2026
Project Planning: WBS, Gantt Charts & Communication Plans
Quick Answer: Project planning translates Six Sigma charter goals into executable operational schedules through the Work Breakdown Structure (WBS), Gantt charts, and Critical Path Method (CPM). The WBS breaks down deliverables following the 100% Rule, ensuring complete scope capture without extraneous additions. Gantt charts map work packages across calendar timelines, while CPM identifies zero-float tasks that dictate minimum project duration. Complementary communication plans and risk registers sustain stakeholder alignment and mitigate operational hurdles. Independent CSSYB study guide by ExamFinch.
The Work Breakdown Structure (WBS)
While the project charter establishes what the team must accomplish, it does not specify daily operational execution. To bridge this gap, teams construct a Work Breakdown Structure (WBS) —a hierarchical, deliverable-oriented visual decomposition of the total scope of work required to complete the project.
A standard WBS organizes project outputs into progressive levels of detail:
Level 1: The overarching project deliverable or goal (e.g., Reduce Electronic Billing Errors ).
Level 2: The primary project phases, typically mapped to the DMAIC lifecycle ( Define, Measure, Analyze, Improve, Control Deliverables ).
Level 3: Sub-deliverables supporting each phase (e.g., under Define: Approved Charter, Process Map, Stakeholder Plan ).
Lowest Level (Work Package): The fundamental unit of the WBS. A work package represents a discrete, manageable unit of work assigned to a single owner, with clear completion criteria, measurable output, and predictable cost and duration.
The 100% Rule
The governing standard of WBS construction is the 100% Rule . This rule requires that the WBS encompass 100% of the project scope defined in the charter—including internal project management activities such as tollgate presentations, team workshops, and baseline audits—with zero omissions and zero extraneous additions. At each downward tier of decomposition, child deliverables must sum to exactly 100% of the parent deliverable. Adhering to the 100% rule prevents scope omissions while barring non-chartered tasks from siphoning team capacity.
Project Scheduling with Gantt Charts
Once the WBS establishes all work packages, the project leader arranges them across an operational calendar using a Gantt Chart . Developed by Henry Gantt in the 1910s, the Gantt chart is a horizontal bar chart displaying project activities against a calendar timeline.
Key components of a Gantt chart include:
Task Identification: Individual work packages and summary rows listed along the vertical axis.
Calendar Timeline: Units of time (days, weeks, or months) displayed along the horizontal axis.
Duration Bars: Horizontal bars whose lengths correspond to planned task durations from start to finish.
Predecessor Dependencies: Visual links establishing task relationships. The most common is Finish-to-Start (FS) , where Task B cannot begin until Task A completes (e.g., data collection must finish before statistical capability calculations can start).
Milestones: Zero-duration checkpoints (often represented by diamonds) denoting major achievements or gate reviews (e.g., Define Tollgate Sign-off ).
Yellow Belts reference Gantt charts during weekly huddles to monitor assignments, track dependencies, and catch schedule slippage early.
Critical Path Method (CPM) and Float Concepts
Complex Six Sigma projects involve multiple parallel activity paths. To determine project duration and prioritize resources, leaders utilize the Critical Path Method (CPM) . The critical path represents the longest continuous sequence of dependent activities from project start to finish .
Strategic Importance of the Critical Path
The critical path determines the absolute minimum time required to complete the entire project. Even if parallel non-critical tasks finish early, the overall project cannot complete any faster than the cumulative duration of tasks along the critical path.
Understanding Float (Slack)
Activities in a project network possess varying degrees of schedule flexibility, termed Float or Slack :
Total Float: The total duration an activity can be delayed from its early start date without delaying the overall project completion deadline ( T o t a l F l o a t = L a t e S t a r t − E a r l y S t a r t = L a t e F i n i s h − E a r l y F i n i s h Total\ Float = Late\ Start - Early\ Start = Late\ Finish - Early\ Finish T o t a l Fl o a t = L a t e St a r t − E a r l y St a r t = L a t e F ini s h − E a r l y F ini s h ).
Free Float: The duration an activity can be delayed without delaying the early start of any immediate successor activity.
The Zero Float Rule: Activities residing on the critical path possess zero total float ( F l o a t = 0 Float = 0 Fl o a t = 0 ). Consequently, any delay to a critical path activity causes an identical, day-for-day delay to the final project completion date , unless leadership applies schedule compression.
To recover lost time on the critical path, project leaders evaluate two compression techniques:
Crashing: Adding resources (e.g., assigning additional Yellow Belts to data logging or paying overtime) to shorten critical task durations, which increases project cost.
Fast-Tracking: Executing sequential critical tasks in parallel rather than waiting for preceding tasks to finish, which elevates operational risk and rework potential.
Project Communication Planning & Risk Management
Technical rigor alone does not guarantee project success; stakeholder alignment is equally vital. Process changes frequently trigger operational anxiety among frontline personnel. To maintain transparency, teams develop a formal Project Communication Plan defining audience, objectives, delivery channels, update frequency, and assigned owners.
Stakeholder Group Core Information Needed Delivery Channel Cadence Assigned Owner
Project Champion Milestone health, budget burn, roadblock escalations Executive Briefing / Dashboard Bi-weekly & Tollgates Belt Project Leader
Process Owner Detailed performance metrics, shift impacts, resource time 1-on-1 Operational Review Weekly Belt Project Leader
Frontline Operators Data collection instructions, pilot testing, procedural shifts Shift Standup / Visual Board Weekly Yellow Belt Contributor
Finance Analyst Validated COPQ reduction, hard vs. soft savings metrics Financial Review Model Monthly & Control Phase Belt Lead & Finance SME
In parallel, teams maintain a Risk Register throughout DMAIC execution. For each identified hurdle, the team calculates a priority score ( Risk Score = Probability × Impact \text{Risk Score} = \text{Probability} \times \text{Impact} Risk Score = Probability × Impact ) and formulates targeted response plans: Avoidance , Mitigation , Transfer , or Acceptance . Yellow Belts assist by monitoring operational triggers during daily tasks.