In my recent article introducing lean manufacturing, I explained that a key part of the philosophy is that skilled workers are engaged in a range of production tasks, as well as setting machines, checking for quality and identifying the root cause of any defects. People who aren’t actually adding value to the product are viewed as muda—waste. Jobs such as inspector, foreman and cleaner should all be replaced by flexible teams of production workers. These teams are responsible for their section of the production line, including doing their own cleaning, repairs and quality checking. That means production workers must keep their work area organized and have a systematic way of doing it, referred to as 5S.
The origin of the term 5S is the names for the five stages in Japanese: seiri, seiton, seisō, seiketsu and shitsuke, typically translated as:
- Sort
- Set in order (or straighten)
- Shine
- Standardize
- Sustain
These five stages provide a method of organizing a workspace so that the items needed most often are always readily to handle while less frequently used items do not clutter the workspace but are still easily retrieved from storage. A neat and tidy workspace makes it easier to find things and leads to more efficient work. A key component of this process is the standardization of procedures and the tools used to carry them out. As with everything in lean, the system should not be enforced on production workers by production engineers. It should instead be developed by the people actually adding value to the product.
The idea that a workspace should be neat and organized is not a new one and did not begin with Lean Manufacturing. The phrase “a place for everything and everything in its place” sums up the basic idea well. Its origin has been lost but perhaps lies with the British navy. In 1842, Frederick Marryat wrote that, “In a well-conducted man-of-war everything is in its place, and there is a place for everything.” 5S is closely related to the idea of the visual workplace and often involves peg boards and tool foam.
Sort
The first stage in the 5S process is to sort through everything in the workspace to remove unnecessary items cluttering the area and identify the important items that need to be at hand. Only things that are used to complete a work process should be in the workspace. The sorting process can be done by separating everything into two piles: needed and not needed.
While deciding which bin to place each item in, the people who work in the space should consider questions such as the purpose of the item, when it was last used, how frequently it is used and who uses it.If there is uncertainty about whether some items are needed in the workspace, the red tag method can be used. A semi-permanent red tag area is marked in the workspace. Questionable items are placed in the area with a red tag identifying what it is, where it’s from, who put it there and the date they put it there. Items in the red tag area are reviewed periodically. If something remains there unused for a period of time, such as a month or more, then it is removed from the workspace.
Items that do not need to be in the workspace can be further classified into categories such as:
- Expired stock
- Does not belong
- To be returned
- Overstock to be used
- Mystery items
- Obsolete items
Sorting the working area primarily increases efficiency by reducing the time wasted hunting for tools and materials. Secondary benefits include reduced distraction, simpler inspection of the workspace, more space available and improved safety through the removal of trip hazards and the like.
Set in Order
The second stage in the 5S process is to set in order all the items required to complete the work processes. That means placing them so they can be found, retrieved, used and put back in place as efficiently as possible, making the work processes run smoothly and efficiently. The following principles should be applied when setting tools and materials within the workspace:
- They should be easy to find, such as being in the visual field of the workers.
- They should be close to hand, minimizing movement or workers.
- They should be easy to pick up and place back in their holders.
- They should be ordered logically, such as following the sequence they are used in the process.
- The most frequently used items should be the easiest to reach.
- Locations should be fixed and clearly labeled or marked so items can be returned and missing items easily spotted. Pictures are better than words for labels.
- Containers should hold the correct quantity to prevent overstock.The two-bin system can be used. The first bin supplies current demand, and the second is sufficient for the replenishment period. When the first bin is empty, a set quantity is ordered.
When setting in order the workspace, the people who work in the space should consider questions such as who will use each item, when will they use it, what is used most frequently, the paths people take through the area, whether it is more logical to group items by type or sequence of use, and what additional storage equipment is needed. Everyone who works in the space needs to be involved. There are likely to be some compromises between different people’s tasks.
Within this discussion, it is often worth considering the wider Lean effort and how waste can be reduced in general. Waste may be caused by the production of defects, workers or machines waiting for upstream operations, tools or materials, unnecessary motion, excess inventory or overproduction, unnecessary processing or rework, or wasted skills. While everyone is talking about what they do, what tools they use and how they move around, it may also be possible to identify how some of these other sources of waste can be eliminated.
Shine
Shine means cleaning and inspecting the workspace. Cleaning makes it easier to spot if anything is out of place or damaged. Shining regularly is important to spot problems and keep everything organized. If something is regularly in the wrong place, maybe it needs a new home. Having a regular shine routine improves the efficiency of production processes, reducing waste and preventing errors. It also makes the workspace safe, easy to work in and a pleasant environment. If everything has been set correctly, a person who is not familiar with the workspace should be able to spot anything out of place within a few seconds. Problems such as leaks, spills and damage become much easier to spot after cleaning.
The workspace should be cleaned on a regular schedule. As a minimum, five minutes should be spent cleaning every day. It’s important that there is adequate lighting while cleaning or it may be easy to miss dirt and signs of problems. A chart should be signed to show who has cleaned the area and when. While cleaning, anything out of place should be put back in its place. Notes should be made of anything missing or any low levels of stock so that action can be taken. If there are any regular sources of messiness or dirtiness then, as with any problem identified within Lean, you should identify the root cause of the problem and correct the process to remove this root cause.
It might seem like everyone knows how to clean up, but it needs to be done right. Just like everything else in Lean, the process needs to be standardized. Ensure that everybody, especially new workers, knows which cleaning materials to use, where they are stored and how to clean equipment. This is especially important if there is a risk of damaging equipment while cleaning.
Cleaning isn’t the most glamorous job, but it shouldn’t be left to cleaners to keep your workspace organized. In Lean, everyone is responsible for the workplace. Not only is this an important opportunity to identify problems, cleaning also gives a feeling of ownership in the space. This helps to build the team spirit and get people invested in the business.
Standardize
Once you’ve been through the initial phase of sorting, setting in order and have been regularly shining for a little while, it’s time to standardize the process. That means ensuring everyone is doing things the same way—the best way we know how at the moment. Procedures and schedules should be created to ensure that the workspace is sorted, set in order and shined regularly. This should fit within the daily routine so that the new practices become regular habits. There needs to be clear roles and responsibilities so that everybody knows what they’re supposed to do and when they’re supposed to do it. Checklists are a great way to clearly and simply communicate procedures. Photos placed on the wall, showing the workspace in its correct condition, can be a useful guide, allowing anybody to quickly see if the workplace is in a normal or abnormal condition.
Standardization between areas can also be very useful in sharing best practices and making it easy for workers to move between different workspaces. 5S makes extensive use of visual clues that show where things go and how they should be. Examples include photos of the workspace, tool foam, floor marking tape, and other signs and labels. These visual pointers are often most effective if they don’t require words to be understood. Over time, they make it natural for everything to fall into its proper place. If people are new to 5S, they will need to be reminded to go through the 5S process at regular scheduled times. In time, it becomes a natural part of being in the workspace that people clean, sort and set.
Sustain
Once the 5S processes have been standardized and are running smoothly, there is a need to ensure they are maintained and updated to keep them relevant. This aspect can include regular audits to ensure that everything is in the right place and there are the right quantities of materials. It is about ensuring that the processes continue to run smoothly and everyone is still involved. It also means ensuring that all new workers, to a given workspace, are trained in the 5S procedures for that space.
Sustain needs to ensure that 5S becomes part of the operational culture of the business and not just a project that gets completed. It is then that 5S becomes an engine for continuous improvement. If it seems like you can’t improve your 5S system any more, then it’s worth taking a look at what other businesses are doing to see if you can learn from them. Making continuous improvements isn’t just about the direct benefits they bring. It’s also about engaging and motivating the workforce.
Safety – The 6th S
Some businesses have added safety to the system, which they now call 6S. This means having scheduled activities to specifically look at how safety can be improved in the workspace. This means identifying any risks and finding ways to reduce or eliminate them. Examples might include lifting hazards, forklifts, hazardous substances or workstation ergonomics.
In traditional 5S, it is assumed that safety will be considered within the other steps, but there is certainly a case for giving it its own focus, perhaps aligned with risk assessments.
Conclusions
Although 5S was created for manufacturing,it is applicable to any workspace. It has had a impact on health care, especially the need to have supplies immediately at hand in emergencies. A lot of people now apply the visual tool management principles in home workshops. It might even be worth applying some of the principles at home to get you and the kids ready and out the door on time in the morning.
5S is one of those things that seems obvious, yet the more you consider it, the deeper it becomes. It is a vital part of the Lean methodology. Keeping the workplace clean and organized makes it far more efficient. That is not only because it’s easy to find what you need to get the job done but also because problems are identified through the 5S process and it builds an invested team.