The Importance of 5S | The first S – Seiri (Sort)
Akinori Hyodo, former Factory Manager, Toyota HiAce Factory | #AskSensei Event 13 Summary | 3 August 2020
In the world of lean, 5S is often considered as the basis for all improvement. When 5S is implemented thoroughly and continuously, it contributes to the elimination of waste and the improvement of workplace efficiency as problems and issues are exposed and visualized much more easily. Lean manufacturing sensei Akinori Hyodo discusses the importance of 5S and explains the idea and purpose of each S in the 5S process over the course of this series of five #AskSensei webinars dedicated to 5S.
First S of 5S – Seiri (Sort)
I will be talking about 5S over the next five #AskSensei webinars from today. I am going to start off by talking about the first S of seiri in Japanese, which is often referred to as “sort” in English.
Now, let me start with the definition of seiri. It’s about identifying a collection of items as necessary and unnecessary, separating unnecessary items from the necessary items and disposing of them. But, something that I would also like to add to this definition is that seiri implies that we should not introduce, purchase or make anything that we don’t need to start with.
Please think about this for a moment. Since we sometimes introduce and make products or items that we don’t actually need, we end up with unnecessary items in our workplace. So, it would be best if we don’t introduce or produce any unnecessary items in the first place.
As you proceed with the first S at your workplace, something good to put in place early on is to have a standard that everyone can understand as to what is necessary and what is unnecessary. However, in doing so we need to recognize that in an organization or a company, there are usually different levels from an operator to a team leader through to a manager and top management. The definition of what is necessary and unnecessary may differ at each level, and therefore it is important that the standard is set as detailed as possible. A quantitative standard around what is necessary and unnecessary is a good thing to put in place.
Let me give you some examples. An easy example for everyone to understand is defective products. Everyone can tell that defective items are something that are regarded as unnecessary. Here is another example that I want you to consider. Let’s say you have a number of welding machines lined up in your process. While some welding machines are used every day, other machines may only be used once every six months. Under such a circumstance, if you ask the operators who are working in that process, they will most likely tell you that they are all necessary items as they all use those machines irrespective of the frequency that they are used. However, when you think about the fact that some of those machines are only used once every six months or so but are still placed in their workplace, you will soon realize this is making the operators’ job more difficult as this equipment is sitting in their workplace all year round, getting in the way of the operators as they run their manufacturing process.
If those above the operators such as their supervisor and manager are looking at their workplace closely and often, they will come to the realization that the particular piece of equipment is in the way of operators and preventing them from working more efficiently. Therefore, it can be moved away from the main work area.
So, if you can conduct an analysis of the frequency of items being used in an area, for example, it becomes a lot easier to go through the decision-making process of what is necessary and what is unnecessary. As I often refer to the scale or unit of time – such as weeks, months, years etc., the larger those units of time become, the easier it is for you to make a decision to identify whether an item is necessary or not.
A great reference regarding first S can also be found in your own personal lives at home. For instance, I bet you don’t keep all of your clothes mixed up and bunched up together in the middle of your bedroom. I am sure you separate those clothes you don’t wear often from those you wear more frequently. I trust that you also dispose of those clothes you don’t wear anymore or those that are old and worn out.
Now, think of your kitchen as another example. I am sure many of you apply the first S of seiri in the kitchen and keep it tidy and functional in general. I bet all the utensils and equipment you use frequently and regularly are kept close-by and located somewhere you can easily access but those that are used less often or occasionally may be stored in a separate area.
The same thinking should be applied to your workplace. This is particularly important when you have limited space. And, when you have to make some strong decisions to actually throw things out and move things on, the secret is to throw things out purposefully with courage rather than let part of your heart want to hold onto them.
When you are trying to implement the first S in your workplace as a basis for your lean factory, but the decision making as to what’s necessary and what’s unnecessary at an operator level is proving to be difficult, having a higher level of the organization observe the work area and provide guidance can be really effective in order to push forward.
The thing about 5S is that it is not something that you attempt just once and finish. This is something that you have to repeat. You must keep on repeating the process forever. That is why it is crucial for those higher in the organization to lead the rest of the organization by example. What will also be helpful with this is to create a model area or an example that you can point to and show people in different areas of business to learn from.
To conclude my introduction of sort and its role within 5S, I would also like to highlight the important objective behind implementing 5S with anything you do. The ultimate objective of doing 5S is to be able to expose the problems you have in your work area. That’s why once you implement the first S, you must make sure to keep things you are left with in good order. I will talk about the second S of seiton or “set in order” as our topic in the next #AskSensei webinar, and will highlight the importance of putting in place clear visual guidelines, rules and standards around what amount or quantity of your items you should be keeping and managing etc. in order to help maintain the level of 5S to keep the gains you achieved out of implementing the first S in an area. This is a very important step as the second S is closely linked to the first S. Otherwise, you will end up doing the same activities you did in the first S over and over again as unnecessary things will be reintroduced again and your work environment will revert back to the state where you started from.
Just even through focusing on 5S and not doing anything else around improvement or lean, you will find that you will achieve an excellent result for your organization if you can implement it thoroughly and continuously. So, I encourage you to give 5S your best shot!
What is your most recommended criteria for sorting?
When it comes to sorting, the first and foremost criteria is to figure out what is necessary and what is unnecessary. As I was referring to before, your own home environment should provide a good reference for what these criteria should be.
For example, as for what clothes you have out in front of your closet, I trust you put your summer clothes out in summer and your winter clothes out in winter. That’s the standard or criteria we have for our clothes throughout the year. With regard to your kitchen, I am sure we put things out depending on the frequency of use. When you cook for your family, for instance, you will prepare the meal based on the number of family members you need to serve the meal for. The number of your family here is the standard in terms of how much food you need to be making at that time.
What I am tying to say here is you need to apply the same thinking at your workplace. This is where I think people may get confused with 5S and the thinking behind it, but it is really about applying the common sense we already use in our daily lives at your work environment.
But, the key part of the secret with the first S is perhaps to have the courage to dispose of those unnecessary items to start with. I have seen on TV the other day what those people who are good at keeping their home environment clean and organized – therefore essentially good at 5S in the house – are doing. The secret is that when they buy something new, they dispose of something at that time as well. So, what happens here is one thing comes in and one thing goes out, therefore the balance is kept even.
Reflecting on the workplace, however, what you see often is that many companies buy and hold onto items and things that they don’t really need. They also produce defects but they are often not disposed of or dealt with properly. As a result, the accumulation of defects is sitting within their companies. In some instances, they make good products but often they don’t go straight out the door to their customers and they end up sitting in the finished goods storage area accumulated as unnecessary items for a long time. So, you must make sure to address those issues thoroughly at your work environment.
Most applications of “sort” come about from disposing of the obvious items that are not necessary. How do you take this to the next level to look deeper at what is really required, specifically quantities of an item? The item may be needed but not in the quantity in the current state.
One of the fundamentals for lean is that we only make what we have sold. This is particularly the case in the world of the Toyota Production System. So, in an ideal situation, we should only be making what we have sold to replace what we have sold, therefore the materials that are sitting in our production area should also only be the necessary amount to produce what have been sold. But, in reality, because we have equipment break-downs, quality issues etc., we tend to buy or hold more materials, tools, equipment, whatever it may be to cover those potential issues and imperfections that we have in our day-to-day production.
When we have all sorts of individuals making their own decisions throughout a company as to what is the necessary quantity to cover those imperfections, we then end up with a great volume of items beyond the necessary amount. However, the more items we have in our workplace the more work and effort is required to carry out our work in this environment. Therefore, the management have to have a good awareness around this.That is why, the management need to make the decision on what is the necessary quantity and set this at a level that everyone must stay within.
In setting the quantity required, there are some formulas that you can work through based on the frequency of use, location of where it is required etc. to come up with the number as to what the ideal quantity should be. So, you should be able to come up with the standard based on your situation. But, frankly speaking, rather than spending too much time in the initial stages of analyzing and coming up with what that perfect number is to reflect your current capability, those at the management level should come up with a number to set as the quantity or the standard that is necessary right now and work with that.
Also, what they really need to do is to work with people’s minds and understanding around what volume is truly required because people generally feel more at ease when they have more items around them because they think they are covered when something goes wrong.
Once the standards and rules are put in place, the management need to pay close attention to the actual workplace and make sure people at the genba level are following those standards and rules. If the management are closely observing the workplace, they will quickly see whether there is too much or too little of any specific item and that standard can be adjusted accordingly as need be.
It is important to remember that your circumstances change over time. So, if you come up with the standard in terms of quantity that is required, you also need to be changing that standard as you improve over time to match your capability. The reason we have extra items or quantity is generally to cover the lack of capability in regard to things like quality and equipment breakdown, etc.
Having said this, we cannot get the quantity down to zero immediately. We need to set a standard stock level that reflects our current capability and as we improve our capability over time, we must make sure to reduce the stock level to match the improved capability.
Do we have to have a register to record items that are disposed of after sorting? Do we also need to ask why unwanted things accumulate and get to the root cause?
With regard to record keeping, it comes down to the company’s policy on these things. While there are many minor smaller items such as stacks of paper that are not usually required to be recorded when disposed, items such as machines, equipment, tools etc. are required to be on record and must be dealt with in an appropriate manner according to the company’s rules. This is particularly the case when those items have depreciation value associated with them. For less important smaller items, you can keep a record if you think that is important. But, I would say that it is not so necessary.
As for the second half of the question in regards to getting down to the root cause as to why unnecessary items are accumulated, the question touches on a great point. I really want to encourage everyone to do this. Why unwanted things do continue to accumulate is most probably because the root cause of why they were introduced in the first place or were left to be accumulated were never thoroughly investigated. Understanding the root cause of why these items were introduced and taking counter measures and actually putting a rule or standard in place to prevent this from happening again in the future is very important. Repeating this cycle over and over again is a really smart way to go about these things.
This must be a continuous process that must go on and the management needs to be following up in this process to ensure counter measures are put in place, a standard is created, etc. As a general rule, those places with a good level of 5S also have a good management philosophy around checking the actual workplace and following up appropriately. However in contrast, in those workplaces with a poor level of 5S we generally don’t see evidence of sufficient follow up from management.
An important side effect of the management looking closely at their workplace and following up on these 5S issues is that their subordinates can see that management are interested and concerned about the level of 5S in their workplace and this changes their awareness which then links to their behavior towards 5S. That’s why it is really important for the management to be involved and engaged with 5S and following up on 5S improvements in order to drive awareness and correct behavior from their employees.
#AskSensei is a regularly-scheduled webinar held together with Shinka Management Senior Senior Lean Consultant Akinori Hyodo, who formerly enjoyed a career with Toyota rising from operator and team leader at Toyota, right up to factory manager and director of Toyota’s HiAce Factory. Each event we cover a different topic related to lean, with participants invited to put their questions to Hyodo Sensei.
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