5S. Prevalent TPS concept that spread everywhere. But somehow, we focused on keeping the initial of “S” more than those meanings. Instead of making a linguistic miracle of 5 words in Japanese & English with the same initials and definitions, I focus on the implications.
“Seiri.” Taichi Ohno has stated in his book that “Seiri” is to throw away unnecessary stuff. Unfortunately, this is not the typical way to use “Seiri.” Rikako Irie qualified for the Olympics, and in her interview, she mentioned that she could not “Seiri” her emotions. She was diagnosed with Leukemia two years ago; what did she have to throw away in her feelings? Something doesn’t make sense.
When I look at the symbols of the word “Seiri（整理）,” I can read in the following ways;
1. Organize based on science/logic
2. Organize the science/logic
These definitions make more sense of the true meaning of “Seiri.” Throwing away unnecessary things is critical. Yet, we often don’t have precise guiding science or logic to decide what is necessary and what is not. As a result, by human nature, we keep as many things as possible. Therefore, the first step is to define those science and logic. This science & logic will take place in the form of standardized work. Standardized work is the crucial starting point of “Seiri.”
A common mistake that happens a lot is to design the standardized work around the 5S. Often I see an operator taking a detour because somebody placed the material. An operator was walking toward the tool, which was somehow located far from its usage point. They had to make such wasted motion because somebody set the 5S without considering the human work. TPS design the processes around human work, and that is respect to human. 5S that forces an operator to move around is not 5S.
5S is the shadow of standardized work.
The Standardized work chart is the perfect guide to do the correct 5S.
Here are some of the things to consider during the “Seiri.”
Points
Location of materials
Location of tools
Information
Lines
Movement of tools
Movement of materials
Areas
Standardized work of the operator
Standardized work of material handler
Zone of each personal
Using these points – lines – areas like a "sun-dial" to understand if the standardized work functioned properly will help us comprehend the problems. The violation location of the 5S is where there were some turbulences inside the standardized work. Problem-solving on the cause of that turbulence will help Kaizen the standardized work that is more stable, efficient, and 5S.
“Seiri” means “Organize the shop floor according to the standardized work.”