Face of Quality
Jim L. Smith
Face of Quality | Jim L. Smith
Should a ninth waste categorization be added?
Expanding Waste

Before I get into the focus of this column, I’d venture to guess that many quality professionals reading this column’s title did an about take thinking this guy has lost his mind. To discover the real intent, read on…
Some readers, like me, might have learned the acronym TIM WOOD to help remember the initial seven wastes of lean, also known as muda (the Japanese term for waste). The seven wastes were devised by Taiichi Ohno, a Japanese industrial engineer who is considered, by many, to be the father of the Toyota Production System (TPS).
Waste is anything that does not add value for which the customer is willing to pay. It is frequently a result of how the system is designed. The seven original wastes which can appear in various orders are arranged in the following way to match the above acronym are transportation, inventory, motion, waiting, overproduction, overprocessing, and defects.
As time progressed, an eighth waste was added and widely accepted: unused talent which some have referred to as neglect of human skills. Considering the eighth waste, a reordering of the eight wastes of lean could produce the acronym DOWNTIME (defects, overproduction, waiting, neglect of human talent, transportation, inventory, motion, and excess processing). This is not the basis for this column, so we’ll not discuss the merits of either as it is unimportant for the theme of this column.
Keeping these wastes in mind, however, when developing a continuous improvement program, we found creating a process flowchart was a great way to target improvement opportunities. Typically, it was helpful to place an entry in red next to the operation and note the categorization of waste which was one of the outcomes. The idea was that the parts of the process in which we could not find the appropriate waste were probably OK, while solutions should be considered that eliminate the muda in red.
Marking on flowcharts or process maps is easy enough, but over the course of several processes, we discovered another (ninth) waste categorization that didn’t fall into one of the traditional forms of muda - Underutilization.
For illustration purposes, consider punch presses or flame-cutting processes. Both processes produce blanks (parts) from steel plates which leave a skeleton behind. I recall thinking about this early in my career when working in what was called first operations which produced parts for future processes. The waste created by multiple operations in large manufacturing firms can be tremendous!
Obviously, this is waste of some form because the entire steel plate isn’t used. Perhaps we’ve maximized its use, and the excess likely is ultimately returned to source for melting and reuse. However, this type of waste doesn’t really fall into one of the traditional seven wastes. It does fit, however, in the underutilized category.
Again, in most situations the excess material may be dealt with by some means but not necessarily considered by a lean manufacturing expert. If it’s identified by a lean professional, it’s because that person is trying to eliminate waste that doesn’t seem to fit in the seven categories.
The seven original wastes are transportation, inventory, motion, waiting, overproduction, overprocessing, and defects.
Reverting to the example of the flame-cutting process, there are times when the skeleton is overused, and because of a lack of spacing between parts, thermal warping can occur, which often leads to defects. It would seem the ideal scenario is one in which we can max out the resources without compromising the robustness of the process.
To avoid confusion with the inclusion of the unused human potential, it was decided to refer to underutilization as “material underutilization.” It became apparent that some confused the two wastes for it was important to include the word “material” to separate it from “human (skill) waste” as well as “waiting” which can be addressed by line balancing.
To focus on this new waste, “material underutilization”, we considered potential solutions. To do this the team started by marking the process flowcharts or process maps or otherwise noted potential areas for greater improvement. Moving forward, the team determined if there was maximum use, so identifying the extent of the waste was the first step.
Significant savings can be attained by increasing number of parts to the maximum level. This would be considered ‘low-hanging fruit’ but it’s an obvious place to start. It not only improves material underutilization but reduces amount of potential waste – a win-win. This is not always going to happen, however, so let’s consider not so obvious steps.
If possible, measure material underutilized waste separately from defective waste. For example, combining non-quality scrap with underutilized material into the same recycling containers can confound the amount of underutilization.
To maximize benefits and reduce waste, investigate changes to the size of supplied material (in this case steel plates). It may be possible that changing the envelope of material to smaller or larger dimensions might be possible to positively affect material underutilization (waste).
Material underutilization is not limited to the examples cited above. It may pertain to various other machine operations, paper-printing environments, or other places in which waste is created as part of the process.
Working on this ninth waste may not fit best in the realm of a traditional lean-only organization, but it doesn’t mean the lean practitioners cannot identify it. For an organization that is more disciplined, for example, one that uses a lean Six Sigma approach, it could lead to significant improvement opportunities. One never knows where a new road might lead, unless it is followed. Sometimes there is no map, so we need to make our own!

