{"id":"error-proofing","model_id":"Error-proofing","name":"Error-proofing","summary":"Error-proofing is a method for helping operators avoid mistakes such as choosing the wrong part, leaving out a part, or installing a part backwards. It is also called mistake-proofing, poka-yoke and baka-yoke (fool-proofing). It is applied through design features and sensing devices that prevent or detect incorrect assembly work.","study_notes":["Also known as mistake-proofing, poka-yoke (error-proofing) and baka-yoke (fool-proofing).","Listed synonyms: Baka-Yoke, Mistake-Proofing, Poka-Yoke.","One example is a product design with physical shapes that make it impossible to install parts in any orientation except the correct one.","Another example is photocells above parts containers that stop a product moving to the next stage if the operator's hands have not broken the light to obtain the necessary parts.","A more complex version uses photocells with additional logic to check that the right combination of parts was selected for the specific product being assembled.","Related topics named in the document: Inspection and Jidoka."],"safety_notes":[],"sources":[{"url":"https://www.lean.org/lexicon-terms/error-proofing/","title":"Error-Proofing - Lean Enterprise Institute","accessed":"2026-10-25"}],"verification":{"status":"source_checked","checked_at":"2026-10-25","values":1,"method":"llm_source_check"},"updated_at":"2026-10-25","type":"operational","spec":{"kind":"methodology","related":[]},"url":"https://machineschema.com/operational/error-proofing","license":"https://creativecommons.org/licenses/by/4.0/"}