A company producing commercial ink products noticed that injury rates during one step in their manufacturing process were rising after the introduction of a new product.
A Lean Six Sigma Master Black Belt (MBB) consultant was hired to help the company try to resolve this serious problem. Was there a simple solution, or would it require considerable resources to stop the injuries?
Let’s learn what the company and consultant did.
Reportable on-the-job injuries and fatalities were rising
The company is a large multinational producer of chemicals with sites in over 90 countries. The problem was occurring in one of their U.S.-based manufacturing locations. This site produced commercial ink for the printing industry. For the past two years, the company’s safety record was very good, with few OSHA reportable accidents and no fatalities. Given that, the site leadership team was very concerned when, during a two-month period, five injuries were reported in addition to two fatal accidents. Something had to be done – and done quickly.
The ink manufacturing process was relatively simple. Once research and development (R&D) developed a new product in the lab, a chemist would then write a recipe and manufacturing instructions to scale it up for large production batches. The raw materials consisted of both powder and liquid components.
Batches of ink were produced in large vats. Bags of powdered raw materials and containers of liquid were opened and emptied into the vats by manufacturing operators. The vats contained a mixing agitator to blend all the raw materials.
While overhead cranes were used to deliver the raw materials to the top of the vats, the operator had to climb a set of 20 steps to get to the platform at the top of the vat. From there, the operator would put the raw materials into the vat according to the recipe and sequenced instructions written by the chemist.
The safety data showed that shortly after a new product and recipe were introduced, accidents started to climb. In two of the seven cases, an operator fell off the platform, resulting in a fatality. The MBB formed an improvement team of operators, supervisors, and safety personnel. Their mission was to find why this was happening and to stop it before any more people were hurt or died.
Trying to find the root cause
The MBB took the team through a series of root cause analysis tools. They started off with some brainstorming on why the problem could be occurring. From there, they did an Affinity Diagram to organize the possible causes. Finally, they did a fishbone diagram to dive deeper to uncover the root cause. Safety data was analyzed to see if the problem was dependent on the shift, day of week, operator experience, or gender, but no obvious reason was uncovered.
After some frustrating meetings with no clear direction as to the root cause, one of the team members suggested the team interview the medical personnel who treated the survivors of the falls. Interestingly, all operators reported they felt dizzy and woozy before fainting on the platform or tumbling down some of the steps at the top. Now the team seemed to be onto something.
The safety department decided to do a quick study and began measuring the air quality at the top of the vat once the raw materials had been emptied into it. They quickly found that by following the sequence of the recipe instructions, the air quality deteriorated because the mixing process released dangerous volatiles in the area of the top of the vat. Volatiles are gasses that are released when certain organic solids and liquids are mixed. One of the key effects from these gasses was dizziness.
Now that the root cause seemed to have been found, they now had to solve the problem.
While it was difficult to find the root cause, the solution was easy
Although the volatile issue seemed to be the reason for operators getting dizzy and falling, the question became: Why are the volatiles being released? The chemist who developed the recipe and instructions was brought into a team meeting to explain why the situation could be occurring. After analyzing her work instructions, she concluded that the sequencing of raw materials was the root cause for the creation of the volatiles – and probably the reason operators were getting dizzy and falling.
One of the team members asked the chemist why she wrote the instructions in that sequence, and if was critical to do it that way.
Her answer shocked everyone.
She said, “No. I just did it that way because it made sense.” She then added, “I can change the sequence easily and don’t see how it would negatively impact the product.”
Was it really that easy?
Rewriting the instructions
The next day, the chemist sat down with three manufacturing supervisors, three operators, and two safety people to review the new instructions. A trial was run a week later to confirm that any changes to the sequence would not have an impact on the process or product,
Additionally, it was decided that manufacturing and safety personnel should be consulted before finalizing any future recipes and instructions for new products. This was not for their chemical expertise but possible safety and manufacturing issues.
The site leadership implemented a process where all new recipes needed to be analyzed using a Failure Modes and Effects Analysis (FMEA). This was done to understand whether there are any possible failure modes that could be mitigated before the new recipe and instructions are implemented and not after there was already a problem.
The Environmental Health and Safety Department (EH&S) put protocols in place to have operators wear respirator masks when loading the vat to prevent any harmful gasses from impacting the operator.
There were no further incidents in the area due to that problem.
3 best practices when implementing root cause analysis and writing job instructions
The challenge for this company was finding the root cause of the safety problem, and then developing a solution. Here are a few tips to help you if you’re faced with a similar situation.
1. Keep drilling to the root cause
If the true root cause was easy to identify, you would have solved your problem a long time ago. In the case above, the root cause wasn’t the volatiles, but the original job instructions written by the chemist. Keep digging past the obvious if you want to truly solve your problem and not just put on another bandage.
2. Involve those who work the process
While chemists, engineers, IT experts, and R&D researchers know the science, it is the operators on the floor who know the process and have to utilize the work of the technical workers. Where appropriate, solicit and evaluate their input on how they may be impacted by the decisions of the technical experts.
3. Don’t be afraid to ask “why?”
Most organizations react negatively when operators question why certain operational decisions are made. It is a good idea to foster an environment where people can ask why something is being done a certain way.
Being on the floor and doing the tasks every day gives operating personnel unique insights into the impact of decisions made elsewhere. As a follow-up to the incident at the ink company, operators sensed something wasn’t right after the first two batches. Unfortunately, the working environment at the organization may have discouraged the asking of questions.
Employee engagement could have saved lives and prevented injuries
Everyone was doing their job the best they knew how. Unfortunately, as Dr. W. Edwards Deming said, “It is not enough to do your best; you must know what to do, then do your best.” The chemist knew her job and wrote a recipe and instructions that were technically correct. The operators followed those directions as they were written. The EH&S people accepted the situation without verifying the safety of the process. Unfortunately, none of that helped the two employees who died or the other five who were injured.
Getting employees involved in decisions which will directly impact their work and safety should be how critical decisions and process changes are made. Piloting new processes is also a good practice. Finally, creating an environment where people are not afraid to ask Why will pay big dividends and possibly save lives.