Module 6 · Lesson 2 of 17
Control-plan construction
This lesson and the entire Lean Six Sigma Black Belt academy are free of charge — no fees, ever.
Learning objectives
- Draft a control plan that keeps the improvement stable.
- Distinguish control characteristics, methods, sample sizes and reaction plans.
- Assign clear ownership so the plan survives the belt leaving.
What a control plan is
A control plan is a single table that tells the process owner what to measure, how often, by whom, with what tool and what to do when the reading is out of limits. If the plan is missing any of those columns it is not really a control plan.
Columns that must always be present
- Process step and characteristic (e.g. cuff opening width).
- Specification and tolerance.
- Measurement method and tool.
- Sample size and frequency.
- Person responsible.
- Reaction plan when out-of-control.
- Record location (paper, tablet, MES).
Garment-factory example
After a jeans-inseam fit improvement, the control plan asks the line auditor to measure five pieces per bundle every hour, log values on a tablet chart, escalate on two consecutive points beyond ±0.5 cm and hold the bundle until the mechanic verifies the folder attachment.
Method
- Draft the plan during Improve, not after Control opens.
- Test the reaction plan on a real out-of-limit case before handover.
- Confirm ownership names — not job titles alone — appear in every row.
Common mistakes
- Leaving the reaction column blank or writing “inform supervisor.”
- Choosing a sample size that the auditor cannot realistically perform.
Knowledge check
Pick one answer per question. Explanations appear after you submit.
1. Which column makes a control plan actually preventive?
2. Whose name should sit in the responsibility column?
Author: NOSK.life · Last reviewed: 2026-07-21