Tag Archives: Error Proofing

Error Proofing

We are pleased to present this guest blog post by Heather Dunne, Digital Services Specialist for University Marketing and Communications at Michigan Technological University.

One of the common tools in Lean and continuous improvement is error proofing, or poka-yoke. Poka-yoke is a Japanese term that was developed and classified by Shigeo Shingo; that helps someone avoid (yokeru) mistakes (poka).

The concept is simple: Create countermeasures that guard against and prevent errors and mistakes from occurring in a process. If mistakes are avoided, the product quality is high, the customer is happy, and money is saved. Workers, engineers, and managers all must work together to write procedures and design devices to prevent errors from occurring at their source. Errors made within any process can lead to problems, including multiple wastes such as defects, overproduction, waiting, not utilizing people, transportation, inventory, motion, and excess processing.

Error proofing is implemented to prevent human error, but human error cannot be accepted as the cause of an error. The blame game does not apply. Humans make mistakes typically because there is a flaw in the process, itself. There are standard steps that can be taken when error proofing a process. First, take a first-hand look at the process, walking the gemba. Secondly, learn exactly where the error occurred. Then, conduct some problem solving analysis to uncover the root cause. Finally, develop countermeasures to prevent that error from happening again.

Some examples of real-world poka-yokes are the sensor in the gas nozzle that clicks when your tank is full, the ice maker in your freezer shutting off when the bucket if full, and your washing machine stopping when it is out of balance.

Michigan Tech’s Housing and Residential Life developed some poka-yokes for summer conferences:

  • A reference visual for staff who are setting up linens for a room.  It lists exactly what linens are needed and shows how they should be placed on the bed.  This saves staff time when gathering linens to distribute and reduces error in forgetting to place an item in the room.
  • Signage informing guests about areas they have access to and areas they do not. Limiting access to certain floors used the ERA principle–Eliminate Replacement Alternatives.  If the task that is creating the error is eliminated, then the error will disappear too.
  • A kanban board for management of the many groups that stay as guests. By arranging items, information, and people according to a sequence, they developed a good mistake proofing solution.

What are some ways you can apply this simple lean concept in your area?


The Perfect Cup of Joe

We are pleased to present this guest blog post by Annelise Doll, Digital Initiatives Librarian at the Van Pelt & Opie Library at Michigan Technological University.

In the fall of 2015, I began training to become a Lean facilitator here on campus and am always excited to apply the many tools and tips I learn in these sessions to my work in the library. This not only improves my work, but also is great practice for when I become a facilitator. Sometimes it takes a new perspective from our discussions to see how I could use a particular tool, but Lean philosophy can be adapted to so many environments that it never takes long to understand how it can be useful. Standardized work, however, escaped me. When I was introduced to the concept, I could see the value right away: improvements in the quality of products, ease of training new people, and the creation of a safer work environment, to name a few. Even so, I struggled with where I could use this concept in my own work. I didn’t have to wait long for an opportunity though, and it came in the form of a coffee maker!

In an effort to increase cleanliness, the library recently implemented a system that recognizes individuals for cleaning the staff lounge. I’m known for regularly deep-cleaning our large bunn coffee maker, and now there are a few more people who’d like to help. Unfortunately, the task requires a few techniques and special pieces of equipment, so when I’m not in the office to assist it can be a difficult task to complete. Standardizing this work by creating a job element sheet certainly seems like the perfect solution to this issue!

Job Element SheetI formatted the job element sheet based on the one used by Catering Services for, coincidentally, making coffee. After picking out the steps involved and taking photos, I realized it would be easy enough to also create a sheet for how to brew a pot of coffee. Maybe it’s my love of the perfect cup of joe, the intimidating nature of a commercial coffee maker, or the fact that it can be difficult for many people to remember how much coffee to use, but for whatever reason I’m also the one who usually makes coffee for staff events. For being such a simple process, I know from experience that there are an outstanding number of ways it can go wrong! I tried my best to draw on this knowledge to help others avoid mistakes like pouring water into the machine without a pot underneath or forgetting to turn the burner off.

I’ve placed the sheets next to the coffee maker in the lounge and will ask for feedback from others in the library who are willing to test them out. I hope that the clarity and sequence of the steps can be improved as time goes on, and maybe the experience will inspire others to use a tool like this in their work. In any event, I’m sure I’ll be enjoying some excellent coffee made by my colleagues in the future!

If you think standardizing your work by creating a similar tool would be useful for you, please share your idea in the comments!

 


Making Safety a Part of Your Lean Practice

Implementing safety and Lean together can help your organization increase productivity by reducing the wastes associated with a hazardous environment. Lean and other continuous improvement methodologies enable a safety-focused environment, by using problem solving and root cause analysis to correct the true cause of safety hazards in the workplace.

Here are some examples of how you can use Lean to make improvements to safety and increase safety awareness in your workplace:

  • Reducing excess inventory helps increase floor space and reduces potential tripping hazards. Other safety related to storage solutions might include avoiding piling boxes or other supplies on top of filing cabinets, shelves, etc.
  • While investigating workplace incidents, the “5 Whys” could be used to get down to the root causes of the accident and make improvements to prevent the error from occurring again. But remember, almost all system failures result from a combination of a number of factors and failures. You must continue to probe the circumstances, rules, policies, and people around the incident to search for all of the root causes.
  • Error-proofing can be used to avoid or prevent safety hazards.
  • Having “a place for everything and everything in its place” ensures that items are put back where they belong, and can be put back in a safe location.
  • When process mapping, safety risks can also be identified as improvement opportunities so that these risks can be mitigated.
  • Tracking  metrics related to safety can help identify any trends that may exist regarding safety incidents in order to identify opportunities for improvement.
  • Standard work can be created for workplace safety procedures in order to ensure that the task is completed safely each time.
  • Safety topics, recent safety incidents, and safety metrics can all be discussed in daily team meetings to increase safety awareness.
Example safety metric.

Those are a few examples of how an organization can make safety a part of their Lean culture. Keep in mind, a successful safety culture requires the same management support and participation as successfully making Lean a part of your organization’s culture!


Calumet Electronics Tour

Recently, Todd Brassard, Vice President/COO of Calumet Electronics, spent an afternoon giving our group a tour of their operations in Calumet, MI. During this tour, we were able to see the complex process (over 40 steps!) that it takes to produce a circuit board. In their manufacturing operations, there were several examples of Lean Manufacturing and Six Sigma in practice. I’ll talk about a few examples that we saw during our tour.

  • Many pieces of equipment had a three-color light (green, yellow, or red), that indicated the status of the machine, an example of andon.
  • Machines that drilled holes into the circuit boards automatically picked the necessary drill bit needed for the particular hole size it needed to drill, and tested the bit prior to drilling any holes into the circuit board. If a bit is damaged, then the red light on the machine comes on (andon!) so that a worker can come to the machine to inspect the bit and address the issue.
  • Workers that inspect the quality of each of the circuit boards worked in a left-to-right pattern in their work area to ensure that untested circuit boards don’t get mixed in with circuit boards that have either passed or failed the quality inspection (error proofing); only the boards that had passed the inspection made it into the stack on the far right of their work area. These workers also test the circuit boards in small batches of 25 that their computer confirms the count of; this ensures that the whole stack of 25 has been inspected before the next batch can be tested. The computer also says, in clear and large text, “Pass” in green or “Fail” in red (a visual control) when telling the worker the results of the inspection.
  • Todd also noted that for many of their process, they are tracking Cpk, which is the actualized process capability. As a rule of thumb, a Cpk of at least 1.33 indicates a capable process.
  • At the end of the tour, Todd showed our group some awesome data collection and metrics that they’ve begun keeping to track the “health” of their business. To the “data geeks” among us, this was pretty neat!