In 1961, an industrial engineer at Toyota named Shigeo Shingo introduced a concept he called poka-yoke—or, in English, “error proofing.”
Also known as “mistake proofing,” error proofing is the act of applying change to a process to prevent mistakes from occurring or to warn that they might occur. The technique is designed to root out human error in production.
After all, human error is an inherent problem any organization faces, points out Duke Okes, a quality management consultant. In a conference for AudioSolutionz, “Using Mistake Proofing to Prevent and Detect Human Error in Production and Office Environments,” Okes explains how to apply the principal of error proofing is in today’s world, using day-to-day examples for application and implementation.
Poka-yoke: More Than an Automatic Shutoff
While error proofing can be achieved with a simple limit switch or optical inspection system, noted Quality Magazine, the concept can be applied to areas beyond production, such as in sales, bookkeeping, and product development.
“The reality is that defect prevention, or defect detection and removal, has widespread applications in most organizations,” the magazine noted in an article titled “Poka-Yoke for Quality.”
Besides identifying problems in the production stage—where they can be incredibly costly—these error proofing techniques also offer companies a competitive advantage, make for more knowledgeable workers, provide better predictability, and reduce variation.
Relying on standard work practices and employee training will only take you so far; such methods can reduce error frequency but not prevent errors from occurring, noted process development consultants Quality-One. Poka-yoke, on the other hand, is focused on eliminating human error and can have “a profound impact on productivity, product quality and employee morale”—not to mention cost savings, according to Quality-One.
When To Implement?
While it’s never too late to introduce error proofing techniques into your processes, overall the practice should be employed “when there is sufficient risk in the process so that failure would adversely affect the customer,” said Quality-One. That can include times when:
- Heightened alertness is needed
- Errors are creating a cascade of problems down the production ladder
- Errors could create safety issues
- Employee turnover is high or retraining is frequently needed
- Incorrect component placement can cause defects
The concept of poka-yoke can’t simply be slapped on any old problem, however, explained Anthony Borges, a marketing manager and author of the article “The Top 7 Manufacturing Pains Today and How to Remedy them” for Automation.com.
Rather, efficiency calls for finding a solution quickly, in a cost-efficient manner, and with a resolution that can be scaled to your system and is flexible enough for use through the manufacturing process.
“Regardless of the finished product type, it is the individual process steps performed by human and machine ‘in a certain way’ that ultimately yields a quality or shippable product,” Borges wrote.
Okes affirms that everyone on your team—from quality managers to safety coordinators and process owners—needs to know the factors that lead to human error and how to detect, evaluate, and prevent mistakes. Your company’s bottom line is at stake.