Quality Management Cheat Sheet

Quality Management — Quick Reference

Quality vs. Grade

• Quality = Degree to which requirements are met. Low quality is always a problem.
• Grade = Category of features/characteristics. Low grade may be acceptable.

Quality Management Process

1. Plan Quality Management — Identify requirements and standards
2. Manage Quality — Translate plan into executable quality activities
3. Control Quality — Monitor and record results of quality activities

Cost of Quality

Category	Type	Examples
Prevention Costs	Conformance	Training, documentation, equipment, time to do it right
Appraisal Costs	Conformance	Testing, inspection, audits
Internal Failure	Nonconformance	Rework, scrap (found before customer)
External Failure	Nonconformance	Warranty, liability, reputation damage (found by customer)

Key principle: Prevention is cheaper than inspection. Spend on prevention to reduce overall cost of quality.

Quality Tools (Seven Basic)

1. Cause-and-Effect Diagram (Ishikawa/Fishbone) — Identify root causes
2. Flowchart — Map processes to find inefficiencies
3. Check Sheet — Structured data collection form
4. Pareto Chart — 80/20 rule: focus on the vital few causes
5. Histogram — Frequency distribution of data
6. Control Chart — Process stability over time (UCL/LCL)
7. Scatter Diagram — Correlation between two variables

Control Chart Rules

• Rule of 7 — 7 consecutive points on one side of the mean indicates the process is out of control
• Points outside Upper/Lower Control Limits = out of control
• Control limits ≠ specification limits (control = process; specification = customer requirements)