Which practice involves stopping the production line when a defect occurs?

Which practice involves stopping the production line when a defect occurs?

• A. Kaizen
• B. Poka-yoke
• C. Heijunka
• D. Jidoka

Answer: (D)

Stopping the production line when a defect occurs is Jidoka—automation with a human touch. The idea is to halt the process at the moment an abnormal condition is detected so defects don’t move downstream, making quality at the source and enabling immediate investigation and containment. This often involves an operator or machine signaling to stop the line (an Andon signal) and fix the root cause before restarting. Poka-yoke focuses on preventing mistakes through mistake-proofing devices, Kaizen on ongoing improvements, and Heijunka on production leveling; none of these impose the automatic line-stop behavior that defines Jidoka.

Stopping the production line when a defect occurs is Jidoka—automation with a human touch. The idea is to halt the process at the moment an abnormal condition is detected so defects don’t move downstream, making quality at the source and enabling immediate investigation and containment. This often involves an operator or machine signaling to stop the line (an Andon signal) and fix the root cause before restarting. Poka-yoke focuses on preventing mistakes through mistake-proofing devices, Kaizen on ongoing improvements, and Heijunka on production leveling; none of these impose the automatic line-stop behavior that defines Jidoka.