Three definitions of what it means to be a quality engineer:
1) The American Society for Quality’s (ASQ’s) Body of Knowledge for the Certified Quality Engineer (CQE) Exam.
2) The use of the approach to designing quality into products and processes, referred to as Parameter and Tolerance Design, advocated by the Japanese engineer Genichi Taguchi.
3) The use of the term to refer to an engineering specialty practiced in large companies as part of the quality assurance function, especially when participating in the development of new products, processes, or systems.
ASQ’s Body of Knowledge for the CQE exam uses the following first and second-level groupings: 2
1. General Knowledge, Conduct, and Ethics
2. Quality Practices and Applications
A. Human Resource Management
B. Quality Planning
C. Quality Systems
D. Supplier Management
E. Quality Audit
F. Cost of Quality
G. Continuous Improvement Tools
3. Statistical Principles and Applications
A. Terms and Concepts
B. Distributions
C. Statistical Inference
D. Correlation and Regression Analysis
E. Experimental Design
F. Acceptance Sampling
4. Product, Process, and Materials Control
A. Work Instructions
B. Classification of Characteristics and Defects
C. Identification of Materials and Status
D. Lot Traceability
E. Materials Segregation Practices
F. Materials Review Board Criteria and Procedures
G. Sample Integrity and Control
H. Statistical Process Control
5. Measurement Systems
A. Terms and Definitions
B. Metrology
C. Repeatability and Reproducibility Studies
D. Destructive and Nondestructive Testing
6. Safety and Reliability
A. Terms and Definitions
B. Reliability Systems
C. Reliability Life Characteristic Concepts
D. Risk Assessment Tools and Risk Prevention
E. Product Traceability Systems and Recall Procedures
Taguchi has defined high quality to be low (or minimum) loss to society in producing and using a product. The minimization of the sum of manufacturing cost (supplier’s cost prior to sale) and quality loss (unnecessary cost to customer after the sale) is the approach advocated by Taguchi. Phadke has defined quality engineering to be “concerned with reducing both these costs and, thus, 3
is an interdisciplinary science involving engineering design, manufacturing operations, and economics.” Taguchi views the design process as consisting of three steps: