Error Proofing Technique
Poka Yoke is a Japanese term that means “Mistake-Proofing” or “Error-Proofing”. Is any mechanism in a process that helps prevent human errors as they occur with the purpose of eliminating mistakes. The importance of using this term is that it helps processes work right the first time. This process can improve the reliability as well as the quality of a product. It is important to take into account that humans are not machines so we can make mistakes. That's why the Poka Yoke is needed.
A few examples where we can see the use of Poka Yoke are as follows:
SIM Cards: The shape of a SIM Card is a rectangle with a cut in one of the corners. The reason this cut exists is so there will be only one way to put it into the phone, making it impossible for the users to input the card the wrong way. For example, if the card was just a rectangle there will be multiple ways to insert it making mistakes more likely to happen.
Email Subject: When an email is written and it is mentioned there is an attachment in it, if the attachment is not included in the email and the send button is pressed, a message will appear with a warning saying there is no attachment in the email.
There are 2 types of Poka Yoke, the detection and the prevention method - later proving to be the most efficient. The detection method is characterized when the mistakes are created and alerted. One example of this Poka Yoke type is when in a factory a piece in one of the products is missing so an alert is created to warn the workers about the missing piece.
On the other hand, the prevention method takes place when the system prevents the mistake from being made. For example, when the weight of the people in the elevator exceeds the maximum, the elevator won’t move, preventing any issues from happening.
The first step for Poka Yoke is to identify the root cause of the malfunction. The second step is to define each of the steps of the process to understand where the issue is coming from. Next, you should identify the different options to resolve the issue using the Poka Yoke technique.
After you identify all your options, select the one that seems most useful and apply it for testing. Once the testing stage is over and after an evaluation, you determine the Poka Yoke is working and then you can apply as part of your process.
In general, the Poka Yoke technique can be applied in many different life aspects. Error- Proofing is something we face every day, from a microwave not working with the door open, to the kitchen and bathroom sink having an outlet to avoid floods.
Poka Yoke can also be used to help improve quality assurance techniques. Once an issue is found that was not caught by the quality assurance regular process, we can apply the Poka Yoke technique to identify the source of the issue and avoid it from happening again.
Alexa Vainstein, Senior Analyst