Friday, 7 December 2018

Poka Yoke for reducing product defects

Poka-yoke is a word in the language of Japan which means "fail-sifting" or "mistake-proofing". The term poka-yoke is use for the mechanism in the concept of lean manufacturing is complete. The operator of machinery and equipment to minimize or even avoid mistakes (poka).

The aim of poka-yoke is to avoid the presence of product with the means of preventing, correcting, and improving human error. This method was adopt by Toyota Production System (lean manufacturing). Originally its name was baka-yoke (meaning "fool-proofing" or "idiot-proofing") but has been convert into a poka-yoke which means smoother.

Poka-yoke ala Shigeo Shingo is divided into three types, namely:



  • Contact Method: poka-yoke is complete in a way to analyze identify the shape of the product, size, color and other physical characteristics of the product.

  • Fixed-Value Method (fixed-value or constant number): poka-yoke is done by way of ensuring some movements and activities that need to be done has been done well. This method will warn the operator if they haven't done the necessary things.

  • A Method of Phase-Motion (sequence): poka-yoke is done by ensuring that all the required processes have been run well.


Poka-yoke is actually more work to prevent the occurrence of errors, not to find the mistakes already happened because, for example, operator negligence due to fatigue or burnout. Poka-yoke is very useful because it can provide solutions to the prevention of errors, even if the operator loses concentration or fatigue.

Shingo understands that in any manufacturing fault may be unavoidable. However, juka poka-yoke has been run properly, the error can be prevented or identified quickly so that the defective product can be avoided.

7 steps to apply POKA YOKE:



  1. Quality Process, the perfect Design with always consider the ability of human, machine and process until zero defects can be reach.

  2. Empowering the existing human resources with increase quality towards understanding/work process. Continuous training to enhance the technical skills and Competencies Based Application Matrix.

  3. Eliminate breakage and waste by applying Map, map Problems causes and preventive action.

  4. Eliminate the causes by always act based on the principles of the 5W + 1 h

  5. Always ensure the start correctly on every activity "Do it Right the First Time"

  6. Not planning and looking for a reason to the problem. But to use the time to find the cause of and the Act eliminates the cause

  7. Always oriented to the continuous improvement (Improvement Continues)


Strategies for Zero Defect


You will not create products that you do not need. The more products you create, then sit in the inventory and increase the chance for the defect. Why it adheres to the "Just In Time" principle. And only when it is really necessary and needs the right amount.

  • Expert in expert looking user therefore, it is important to build the safety of the production process. To ensure that the product can cope with any use.

  • Quality products can be complete by fully implementing Poka Yok. Automation and work standardization.

  • If a product cannot be manufacture to use a product. Then make sure that its use is only possible using a continuous flow production.


The fact is, human goings are very forgetful and tend to make mistakes. Too often we blame people for making mistakes. Especially in the workplace, this attitude not only discourages workers and lowers morale, but it does not solve the problem. POKA YOKE is a technique for avoiding simple human error at work.

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