What is Poka Yoke

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Poka Yoke is used to eliminate defects and mistake proof systems, making it impossible to create an error. Even though you haven’t heard of Poka-Yoke in the past, you are surrounded by it and using it on a daily basis.

What is Poka Yoke

Poka Yoke is a devise or method that prevents people from making mistakes. The word is from the Japanese language and means “mistake proofing”.
Poka Yoke It was developed by Shigeo Shingo who wrote the works on the technique, but it was not him who invented it, as the idea of Poka Yoke has been around for a long time.
Originally the technique was called fool or idiot proofing, but it was later changed as it was seen as demeaning towards those using the devices. After all, even the best of us make mistakes.

Defects and Mistakes

Defects on products are always bad for businesses and affect brand reputation or in worst case put people in danger.
When differentiating between mistakes and defects, then Shigeo Shingo defined defects as mistakes that was not detected and managed to get through to the costumer.

Poka Yoke and Quality Control

When looking at Quality Control, then it can be split up in following three categories.

Judgement Inspection: This is where an inspector inspect the parts for defects, using this method is usually very expensive and not that efficient, as even 100% inspection have been found to be only 80-85% effective in best conditions.

Informative Inspection: This is where techniques as SPC is used to monitor the process conditions and can provide valuable information for Continuous Improvement of the process.

Preventive: This is where a technique as Poka Yoke is used to eliminate the defects to be produced in the first place. Since Poka Yoke is designed into the process or part and eliminates the defects from being produced, it makes it very cost effective compared to sorting them out afterwards as seen with inspection. Savings can be seen on less recourse and material use, as well as the impacts of lost costumers due to faulty products.

Everyday Examples of Poka Yoke

There are examples of Poka Yoke everywhere in our daily life, below are a few examples

  • Car key can be inserted with either site up.
  • Overflow drains on sinks, the hole at the top of your sink prevent it from being over full.
  • The gas nozzle shut off the pump when your tank is full to avoid mess and dangerous situations.
  • Computer cables that can only be inserted in a particular way.

If you are interested in implementing various types of Poka Yoke techniques in your business, whether it is related to manufacturing, design, service or something else, please feel free to contact us and see how we can help.

Alternatively then our 8D Problem Solving Training or FMEA Training might be interesting for you, as they also cover Poka Yoke as part of the training.

Poka Yoke