The debate continues

The following paragraph was written by Jack West and Charles Cianfrani in the December 2009 Expert Answers column : "It is acceptable to many to use continual and continuous interchangeably. The ISO standards specifically chose to use the term ‘continual improvement’ because the developers understood it is impossible for improvement to occur uninterrupted."

I wish someone would tell Toyota this. Perhaps then some of its American counterparts, who practice periodic or continual improvement, could finally catch up. Toyota gave us the word kaizen, which has become as much an American word in business as it is a Japanese word. Kaizen means continuous improvement, or improvement occurring uninterruptedly. It’s more synonymous with single-piece flow improvement efforts, rather than doing improvement in batches (Six Sigma projects). It’s about the little improvements made every day by everybody.

It is possible for an organization to continuously improve, and it should be encouraged. Toyota and some American companies that have tried to emulate the Toyota culture (although not the tools, such as 5S) have proven this.

So, as ISO 9001-certified companies and the quality professionals who manage the quality management system continually—or periodically—improve in reaction to customer complaints, internal audits or monthly performance data review, some of our lean counterparts are trying to build continuous improvement cultures. They’re doing this by instituting business elements, such as standard work for leaders, visual controls or management, daily accountability meetings, leadership, gemba walks, and quick and easy kaizen.

Even the late, great W. Edwards Deming gave us his fifth point: Improve constantly and forever the system of production and service. The word "constant" from Google’s dictionary is defined as ceaseless or uninterrupted in time. Deming was also trying to get us to build systems and cultures that continuously improve.

I believe the developers of ISO 9001, up until this point, are missing out on a great opportunity to further improve the standard and further align it with the lean efforts going on worldwide. I hope this issue is addressed (once again) as the process of preparing the next edition is initiated.

The words continual and continuous should not be used interchangeably. Many U.S. companies have been very good at continual improvement (projects performed by Six Sigma belts and other quality people), not continuous improvement (little improvements made every day by everybody). A focus on continuous improvement would further bolster and encourage another ISO 9001 principle: involvement of people. 

Mike Micklewright
Quality Quest Inc.
Arlington Heights, IL

Reworking a definition

In the November 2009 issue of QP, the question of repair vs. rework was asked by Jill Short in Expert Answers. The definition in the answer by Pradip Mehta is taken from the International Organization for Standardization, but the interpretation is different from my understanding. Having worked in manufacturing and new product development for almost 20 years, I can attest that the question of rework vs. repair is very important because it involves additional resources and customer satisfaction.

The difference between repair and rework is clearly defined: It is whether the action will result in an item that conforms to the originally specified requirements. Rework will yield a fully conforming item, while repair will yield a nonconforming item that nevertheless meets the intended usage requirement.

Consider this hypothetical situation. A wooden chair is made from oak. One of the legs has a defect (shorter than others), and the chair is rejected. Because the chair does not meet the specified requirements, it must be corrected.

If the wooden leg is replaced by a good leg from the stock by returning it to the same manufacturing line (in other words, it must follow approved technological process), it will be considered as rework. The product meets the specification because the chair will fulfill the originally specified requirements. There is no need to completely redo the process as Mehta suggested. It can start from the step that is deemed appropriate to allow the product to meet all specified requirements.

There are several scenarios involving repair (some admittedly more hypothetical than others):

  • Replace entire leg with the leg from another material (for example, maple).
  • Replace with the original part (oak leg) without introducing it to the manufacturing line (at the dealer, for example).
  • Add to the defective (short) leg a portion from the same material (oak) to meet the length requirement.
  • Cut the other three legs to match the length of the short leg.

These and similar actions would be considered repair because the product "will fulfill the intended usage" (one can sit on it), although it is "not confirming to the originally specified requirements" (the leg is not made from one piece, the chair is not entirely from oak or the height of the chair is wrong).

It is a very good suggestion from Mehta to develop a company’s definitions standard to minimize variations of interpretation in different areas of the business. It may also be beneficial to have a terms-and-definitions standard specific to each department or unit of the organization to avoid dealing with an overwhelmingly large single document.

Natalia Tirpak
ASQ Senior Member
Winter Park, FL

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