Point-of-Use Storage vs. 5S
Which of these two systems of organization is more appropriate depends on how often the items that need to be organized are used.
There are two lean concepts that, on the surface, appear to have conflicting objectives. Point-of-use storage (POUS) advocates for keeping the items you need to do your job in the work area. Its purpose is to eliminate waste of motion or time spent looking for the things you need when you need them. On the other hand, 5S, the tried-and-true system of workplace organization, stresses sorting out items in a work area; in fact, sorting is considered the first “S,” as it should be completed before you begin the other four (set in order, shine, standardize and sustain). One of the purposes of 5S is elimination of clutter, also known as that collection of things you think you need but really don’t.
Is there common ground where these two concepts can coexist? The answer is yes, but frequency of usage must be a major deciding factor in the POUS vs. 5S conflict.
Frequency of usage may seem like a subjective criterion, and it can be if you allow it to be defined by terms like “once in a while,” “pretty often” or “when I need it.” However, with a little more effort, we can create usage frequency guidelines to help us decide whether something should be left within the confines of a work area or removed after use.
Some usage frequencies make the decision about whether POUS or 5S sorting out is the better approach an easy one. Anything used multiple times in a day is certainly a candidate to be kept in a work area, whether that’s an area on a workbench, a drawer inside the workbench, or even on a board or shelf above the workbench. Conversely, something used less than once a month should be put away somewhere else. These are two extremes to start with, but it’s the usage frequencies between them that can be a little tricky and may require consideration of other factors. Such other factors might include an item’s size, weight, ease of movement/maneuverability or structural integrity. (Does moving it cause damage, or the need for recalibration or lengthy re-setup?) Also important to consider are other places where the item is used, and whether or not it can be moved safely.
Say, for example, a special hand-held tool has a usage frequency of every two or three weeks in different areas of the plant. In this case, the tool should be put away in its designated location after it is used. What’s more, it really would not make sense to keep such a tool on a workbench for those two or three weeks that it is not needed, because it would just clutter up the workbench (especially if accompanied by a half-dozen other special tools with similar usage frequencies). On the other hand, say a similar hand tool is used weekly, but only in one location in the plant. With no competing demand for it and because it is small enough to easily store in a designated location on a workbench, this tool should remain at its point of use.
Here’s another example: A high-precision indicator used to measure close-tolerance parts sits in a special enclosure and is used every three to four weeks when a certain family of parts is run. Although the indicator can be moved, it would need to be requalified for use when it is brought back to this area of the shop. This would take about an hour and tie up a valuable quality-control resource. All things considered, it would be preferable to leave this indicator at its point-of-use, and avoid the time and cost associated with requalification. This decision could be re-evaluated if the
indicator’s frequency of use decreases in the future.
A final example involves a bar-feed attachment that is only used on a few jobs that run every two to three weeks, on average. The attachment is difficult to put on the machine and actually was designed to stay on once attached. It can easily be moved out of the way when not needed. In this case, some forethought and design ingenuity has actually resolved the POUS vs. 5S conflict for us, as the attachment is where it is needed when it is needed, but out of the way when it is not needed.
As we all know, in business, things are rarely “always” or “never.” POUS and 5S are both proven concepts that can reduce waste and improve operational effectiveness. In those cases where POUS and 5S appear to be in conflict, creating some guidelines will help you decide which will work best for you and your operation.