6S (Safety + 5S) is a very simple lean tool that, when implemented well, directly impacts productivity. It therefore forms the foundation of my Lean house for the Shopfloor, which I in 2017 transformed into the first level of lean maturity (Panneman, 2017). 6S improves productivity by reducing Muda (for instance products waiting to be worked on) Mura (for instance variance in cycle times because employees have to search for tools) and Muri (people getting stressed because of they can’t find the right tools in time to keep takt). 6S helps to keep only the necessary items at every workstation (sort), it prevents having people search for items (Straighten), helps people discover problems in an early stage (Sweep) and visualizes the agreements at every workplace (Standardize). Finally these tools need to be used and improved continuously (Sustain). In theory this sounds easy, but what about putting 6S to practice?
The following screenshots show how we have implemented each of the 6 S-es in our factory. Each of the tools play their part to make sure that a tidy workplace is not a one-time thing, but an ongoing philosophy.
SAFETY [illustration 1] is the most important S of the six. All standard way of working methods should result in the description of safest possible way to perform the task, since a task should never take its toll on the health of the people performing it. Next to that, overburdened people in time lead to malfunctioning and therefore to more production errors. Focus on safety in production can be kept by doing dedicated safety-audits.
The tool to use for SORTING [illustration 2] is the Red Tag Zone. The Red Tag Zone is a place in the factory where all materials and tools can be put which are labeled ‘unnecessary for my tasks’ by operators.
STRAIGHTENING [illustration 3] can be facilitated by using colored lines on the flour andshadow boards on the walls. Marking standard locations for tools and material help you identifying missing parts.
SWEEPING [illustration 4] is done regularly by operators. Each team or individual should have their own dedicated machines or workstations to clean at a certain interval. Cleaning by operators is important because nobody knows a machine better than the people who daily use it. While cleaning, small abnormalities can be discovered before it might result in defects. A map of the plant with color coded areas for different teams can be used to visualize the Sweeping standard.
All agreements on Straightening and Sweeping should be documented in a visual standard, by STANDARDIZING [illustration 5]. Every workstation should include one A4 document with a picture of the ideal state of the workstation, including the sweeping schedule.
The sixth S stands for SUSTAINING [illustration 6] and is the most difficult to implement in practice. The tool we use is kamishibai. Kamishibai is a Japanese term for a mini audit tool in shape of a T-card system. By writing short questions on a T-card, everyone can do a mini-audit. The cards can include questions like: “is everybody wearing their protective equipment?” or “are all materials placed on their standard location?”.
Personally I believe the Red Tage zone (for Sorting) and Kamishibai (for Sustaining) are the most important tools to use to keep 6S as ongoing process instead of a one-time cleaning-up session. Using the Kamishibai, Items can constantly be moved to the Red Tag Zone when it does not belong on a workstation. Placed in the Red Tag Zone, everybody has the possibility to remove the found item and bring it back to the workstation it belonged to, or – when it turns out it did have a function– a fixed location can be created on the workstation where it was found.
Finally, since the goal of 6S is to improve productivity: when your 6S program has not lead to measurable resuls, you have probably not used the tool to its fullest potential yet! Use waste walks and spaghetti diagram analysis to improve the way of working as soon as you define your first standards. This makes 6S more than a cleaning excersize, but a proper improvement activity (Panneman, 2017).
This is article 2/5 from the series ‘Lean House for the Shopfloor‘
Standard Work in Practice
*This article forms the basis of one chapter of the book Lean Transformations. The book further explains the link between 5S and the three enemies of lean, and how you can make it the perfect starting tool in a Lean Transformation.
Panneman, T, 2017, Lean Transformations - when and how to climb the four steps of Lean maturity, Maarssen (NL): panview (summary / order this book)
and finally: an interesting 11 minute video from DTPNHS,
Explains how 5S can be applied in more environments than just manufacturing: