Prevent mistakes with the Poka-Yoke System

At a certain point in its history, Toyota was experiencing a small problem with its products. Some customers complained that the factory-produced switches simply didn’t work. The failure happened for a simple reason: some switches were being mounted without a spring, and this prevented their operation.

After several conversations with the team of assemblers, the solution found by Shigeo Shingo, brand engineer, was relatively simple. He instructed the workers when assembling the switch to place all the pieces of equipment on a plate. At the end of assembly, the plate should be empty. If any parts were still there, the assembly was incorrect. And the result of this was the elimination of the issue forever.

This is one of many examples that illustrate the Poka-Yoke methodology, which can be translated as “failsafe”. This is a very effective system for solving operational difficulties, which is why it is widely used by organizations.

But what does the Poka-Yoke System mean?

The Meaning of the Poka-Yoke System

The logic behind the procedure illustrated by Shigeo Shingo, creator of the method, is very simple: production would only continue if a specific step was fulfilled — in this case, the plate was empty.

This logic is extremely useful in several programs in the business environment, as it prevents procedural failures. Poka Yoke then consists of locating key points in the process and subjecting them to some condition. If this condition is not met, the process does not continue.

In addition to preventing errors, poka-yoke also brings another huge benefit: processes are leaner. Like the 5S Program, it helps to organize activities around the optimization of procedures.

This preventive culture is very beneficial for an organization, as it avoids unnecessary expenses with rework and corrections.

How to Apply Poka-Yoke

1 – Identify the problem and its cause

The error in a process can be identified in many ways. Nowadays, there are many tools to identify problems in a process, and one of the most used is the Ishikawa Diagram.

It is important that the identification of this difficulty is as specific as possible, gathering as much information about it as possible. With accurate data and metrics, it is possible to make more assertive decisions, and the solution tends to be simpler when the causes of the issue are more specific.

2 – Think of a preventative solution to the problem

After identifying the failure in the process, it is necessary to find a way to prevent it from happening. This solution may involve several factors, from exchanging resources to changing certain habits in the process.

It is also indispensable that this solution be as simple as possible, considering both the ease of execution and its cost for the company. Completion of this stage of the process must be conditioned on the solution of the identified problem.

3 – Test, analyze and remind

It’s no use applying a solution and not checking if it works, right? So, at this stage, it is necessary to monitor and measure the results. This allows for periodic adjustments to the process and constant optimization.

It is also important to register the program, this can be extremely useful for the implementation of new improvements in the future.