Six Sigma Black Belt Certified Practice Exam

In Lean methodology, what does the term "poka-yoke" refer to?

1. A quality assurance process

2. A tool for process mapping

3. An error-proofing mechanism

4. A waste reduction strategy

The correct answer is: An error-proofing mechanism

The term "poka-yoke" is derived from Japanese and translates to "mistake-proofing." In the context of Lean methodology, it refers specifically to mechanisms or devices designed to prevent errors or defects in a manufacturing or service process. The goal of implementing poka-yoke is to ensure that processes are designed in a way that mistakes are either impossible to make or easily detected and corrected. By doing so, it increases overall quality and efficiency, directly aligning with the principles of Lean focused on streamlining processes and reducing waste. Poka-yoke can take various forms, including physical devices that prevent incorrect operations, checklists that guide staff, or even signals that alert workers when something is out of specification. This proactive approach to quality assurance makes it a crucial concept in Lean continuous improvement efforts. Understanding this concept underscores the importance of integrating error-proofing mechanisms into processes to enhance reliability and maximize efficiency, which is central to Lean principles.