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Poka Yoke is a quality management concept developed by a Matsushita manufacturing engineer named Shigeo Shingo to prevent human errors from occurring in the production line. Poka yoke (pronounced "poh-kah yoh-kay") comes from two Japanese words - "yokeru" which means, "to avoid", and "poka" which means "inadvertent errors." Thus, poka yoke more or less translates to "avoiding inadvertent errors".
Some people as "fool-proofing" sometimes refer to Poka yoke in English. However, this doesn't sound politically correct if applied to employees, so the English equivalent used by Shingo was "error avoidance." Other variants like "mistake proofing" or "fail-safe operation" have likewise become popular.
The main objective of poke yoke is to achieve zero defects. In fact, it is just one of the many components of Shingo's Zero Quality Control (ZQC) system, the goal of which is to eliminate defective products.
Poka Yoke is more of a concept than a procedure. Thus, its implementation is governed by what people think they can do to prevent errors in their workplace, and not by a set of step-by-step instructions on how they should do their job.
Poka yoke is implemented by using simple objects like fixtures, jigs, gadgets, warning devices, paper systems, and the like to prevent people from committing mistakes, even if they try to! These objects, known as poka yoke devices, are usually used to stop the machine and alert the operator if something is about to go wrong.
Anybody can and should practice poka yoke in the workplace. Poke yoke does not entail any rocket science; sometimes it just needs common sense and the appropriate poka yoke device. Poka yoke devices should have the following characteristics:
1. useable by all workers;
2. simple to install;
3. does not require continuous attention from the operator (ideally, it should work even if the operator is not aware of it);
4. low-cost;
5. provides instantaneous feedback, prevention, or correction.
Of course, error proofing can be achieved by extensive automation and computerization. However, this approach is expensive and complicated, and may not be practical for small operations. Besides, it defeats the original purpose of poka yoke, which is to reduce defects from mistakes through the simplest and lowest-cost manner possible.
Poka yoke is at its best when it prevents mistakes, not when it merely catches them. Since human errors usually stem from people who get distracted, tired, confused, or demotivated, a good poka yoke solution is one that requires no attention from the operator. Such a poka yoke device will prevent the occurrence of mistake even if the operator loses focus in what she is doing.
Examples of 'attention-free' Poke Yoke solutions:
1. A jig that prevents a part from being misoriented during loading
2. Non-symmetrical screw hole locations that would prevent a plate from being screwed down incorrectly
3. Electrical plugs that can only be inserted into the correct outlets
4. Notches on boards that only allow correct insertion into edge connectors
5. A flip-type cover over a button that will prevent the button from being accidentally pressed
by designing your system to go one way and not any other way, it means that you are controling the results and the outcome (this is actually the quality assurance concept if you think about it).
for example, you are working in the laboratories where you have glassware and they can be used to test drinking water and test waste water as well.
if you think about it, oh oh, cross contamination alert!!!
now imagine if the glassware can't be moved from the testing area. the analyst can't use the waste water glassware in testing the drinking water. there is no worry about cross conatmination, and you don't even have to write GLP instructions for using glassware.
some equipment use this concept to prevent the use of equipment if a verification is needed.
for example, if you want to start the engine while the gear is in "D", it wont work - Poka Yoke.
another example, some equipment won't work if there is a veiberation around them. while other equipment will stop working after certain being used for certain time period or certain number of samples unless you verify the equipment first
Poka Yoke is a method of "preventing human mistakes or machine defaults or system errors". It is a part of Lean Thinking/Lean Manufacturing world.
It is not for Quality Management, Quality Management is a different matter from preventing defaults/errors. But Poka Yoke is a part of starting point of an effective Quality Management.
i.e. an operator drill a hole in worong place at a work-piece because it looks symmetrical. You can apply a good fixture and solve the misplace of the part into machine. But it is not a Quality Management way, it is a matter of PROBLEM SOLVING by Poka Yoke.
About your question, if you would like to make Poka Yoke as a part of quality system management as a concept, you better create some people who have problem solving culture by poka yoke in the shopfloor. If you create the culture then Poka Yoke is a good concept for contunious improvement as quality management system.
by deming wheel
POKA YOKE is a Japanese word, it means "mistake-proofing". Poka-yoke is a tool in a lean manufacturing process that helps an equipment operator avoid mistakes . Its purpose is to eliminate product defects by preventing, correcting to human errors as they occur.
This is waste elimination. It is a lean concept to enahnce operations effeceincy.
Eliminating waste is a free quality improvement technique. Here you can improve quality and reduce cost contrary to the long beleived concept that extra quality means extra cost.
Waste elimination improves the process and consequently increase the quality of the outcome.
Poka-Yoke: a simple idea that eliminates defects. Yes, makes it impossible to make an error. We are surrounded by Poka-Yoke kind of devices
Even if you have never heard of Poka-Yoke you have certainly used more than one. Perhaps even on a daily basis. Poka-Yoke is as old as the ancient floppy disc (which can be inserted into the drive one way only), or perhaps even older.
Poka-Yoke is a device or method that prevents people from making mistakes. The word in Japanese means mistake proofing or error proofing. Originally the word Baka-Yoke or idiot proofing was used, but someone probably figured that even those of us who are not idiots make mistakes at times so now we use the word Poka-Yoke, and no reference to stupid people is made.
As an example of a daily routine Poka Yoke device is the flash drive (Flash Memory,Bin drive) which can only be pluged to the PC USB drive in a certian way
It is a concept of working system to reduce errors which may be useful to accompanied with six sigma statistical system for continual improvement.
