The Poka-Yoke lean management tool is all about mistake proofing, or avoiding errors within your organisation. This ensures that the appropriate conditions are in place prior to a process or new step being executed, which will stop defects in the first place.
Sometimes it is not possible to detect where a defect may come about before it has occurred. In this instance, poka-yoke will act as a defence function.
It stops errors as soon as possible by bringing attention to the error that cause it (whether this be human, mechanic or process based).
This may involve adding design features that will make it impossible for errors to occur, or reevaluating the whole process therefore ensuring quality products and services.
Most organisations will have processes that can allow for mistakes to be made along the way. If your organisation adopts the poka-yoke tool, this will help in decreasing the errors made.
Mistake proofing techniques (poka-toke) will support your organisation and its customers in many ways, such as:
As mistakes can be made anywhere in the business, this means that Poka-Yoke can be implemented anywhere across the business. An organisation can apply Poka-Yoke to any type of process, helping it prevent errors.
The steps in implementing Poka-Yoke are as follows:
Identify the Process or operation that it needs to be applied to.
This rule is as simple as the name suggests, and is where you must ask yourself ‘Why’ 5 times consecutively in order to find out why something is occurring or behaving that way. By doing this, you will slowly but surely be able to peel away the layers to a problem, eventually finding the root-cause of it. More often than not, the supposed answer to your question will actually lead to asking another question rather than the final solution.
In regards to the Poka-Yoke technique, let’s use the example of customer satisfaction being low around the products they are getting delivered. The 5-why analysis may look a little something like:“Why are the products shipped not meeting satisfactions?” Because they are taking longer to get there than when initially said
As you can see, a root-cause has been found, which was down to a training issue. Now that the organisation is aware of this, they can allocate some extra time to this training and implement steps that will allow them to send products on time.
Don’t get too caught up on the name - ‘why’ may only need to be asked 2 times in order to find out the root-cause of a problem, or conversely, it may need to be asked 15 times. This will depend on the length and scope of the process you are investigating and how many people are involved with it.
Select a Poka-yoke approach that is appropriate to the process
Depending on what has been chosen, an operator will either be alerted before a mistake is about to be made, not allowing the process to carry on any further, or they will be alerted right afterwards, allowing them to step in and intervene.
This may take some time depending on the scope of where it is being implemented. It is important not to rush this step as is the method selected does not work during the test, it won’t in real life either.