Skip to content


Flier announcing envet on the topic of Mistakeproofing 2024-03-13 LCI NorCal

People make mistakes – to err is human – but we can reduce the likelihood that a mistake will occur or alleviate the impact of a mistake that has occurred. This evening we will play with special poker cards to learn to see practices of mistakeproofing in construction. You will hear about a framework that distinguishes 6 principles of mistakeproofing and categorize examples according to these principles to learn why some mistakeproofing practices are better than others. Then we can share other examples that come to mind and talk about how to create your own.

Iris is a Distinguished Professor of Engineering and Project Management, and she directs the Project Production Systems Laboratory (P2SL) at UC Berkeley. She has been teaching lean construction for more than 30 years, using Serious Games such as the Parade of Trades to bring hands-on learning into the classroom. At Cal, she teaches two semester-long graduate courses on Lean Construction. The Mistakeproofing Game she created is based on her research on safety and quality management in construction. Iris is an active member of the International Group for Lean Construction. She is a founding member of the Lean Construction Institute and was recognized as a Lean Pioneer by the Lean Construction Institute (LCI)

13 March 2024, 5:30 PM – 8:00 PM

Texas Back Forty BBQ
100 Coggins Drive
San Antonio Room – Second Floor
Pleasant Hill, CA 94523 

Mistakeproofing Resources

Glossary of Terms

  • Mistakeproofing (also spelled mistake proofing or mistake-proofing): Mistakeproofing “or its Japanese equivalent poka-yoke (pronounced PO-ka yo-KAY), is the use of any automatic device or method that either makes it impossible for an error to occur or makes the error immediately obvious once it has occurred. It is a common process analysis tool.” ( visited 2024-02-14)  — Also called poka-yoke, errorproofing, failsafing
  • Work Operation Framework: a depiction of mistakeproofing interventions one can take either before or after a mistake occurs.

For additional definitions of terms, consult the P2SL GlossaryThis glossary is a work in progress. Email us if a term needs further clarification or if you wish to suggest that other words be included.


Tommelein, I.D. 2023. Mistakeproofing game guide for facilitators. Project Production Systems Laboratory, UC Berkeley, 4 February, 7 pages, to be used with poker-card deck with examples.

Tommelein, I.D. 2019. “Principles of Mistakeproofing and Inventive Problem Solving (TRIZ).” In: Proceedings of the 27th Annual Conference of the International Group for Lean Construction (IGLC 27), Pasquire, C. and Hamzeh, F.R. (eds.), Dublin, Ireland, online at – Best IGLC Paper: Second Place Award.

Tommelein, I.D. 2008. “‘Poka Yoke’ or Quality by Mistake Proofing Design and Construction Systems.” In: P. Tzortzopoulos and M. Kagioglou (Eds.), Proceedings of the 16th Annual Conference of the International Group for Lean Construction, (IGLC 16), 16-18 July, Manchester, UK, July 2008, pp. 195-205, 

Tommelein, I.D. 2008. “Mistake-Proofing Design and Construction Systems Improves Quality of Capital Projects.” Tradeline Leading-edge Resources for Facilities Planning and Management, November 19 (this document used to be online at

Tommelein, I.D. and Demirkesen, S. 2018. Mistakeproofing the Design of Construction Processes Using Inventive Problem Solving (TRIZ). Final Report for CPWR Small Study No. 16-3-PS, CPWR, Silver Spring, MD, 60 pp., available for free download from

Tommelein, I.D. and Yiu, K. 2022. “Mistakeproofing framework and applications in civil engineering operations and products.” ASCE, Construction Research Congress 2022, 9-12 March, Arlington, VA, pp. 617-626,