Green Belt case study: How Elisa Iribarren reduced waste in cosmetics manufacturing

At The Lean Six Sigma Company, we believe the true value of Lean Six Sigma lies in the combination of personal development and measurable business impact. A recent Green Belt project completed by Elisa Iribarren at a global beauty manufacturing business’s site in Ashford perfectly demonstrates both.

Having started her Green Belt training in March, Elisa has now successfully completed the programme by delivering a project that generated significant operational improvements, substantial financial benefits, and lasting capability within the organisation.

Supported throughout her journey by Master Black Belt Dean Arnold, Elisa applied the DMAIC methodology to tackle an important manufacturing challenge, ultimately delivering savings that are many times greater than the investment in the Green Belt programme itself.

Identifying the opportunity

Elisa’s project focused on reducing product losses that occur during barrel change operations within the liquid manufacturing process.

While performance data was already being collected, there were concerns regarding the consistency and reliability of the measurement process. Operators followed slightly different working methods, measurements were not always recorded consistently, and management lacked confidence in the data available to make informed decisions.

The challenge was not simply to reduce losses. First, the organisation needed to establish a reliable and repeatable process that would provide trustworthy data and create visibility of performance.

This became the starting point for Elisa’s Lean Six Sigma project.

Following the DMAIC roadmap

Define: Understanding the problem

During the Define phase, Elisa worked closely with production teams, Team Leaders, Process Engineers, and key stakeholders to understand the process and identify customer requirements.

Using tools such as SIPOC analysis, stakeholder analysis, Voice of the Customer, and CTQ flowdowns, she established a clear project scope and defined the key metrics that would determine success.

The project focused on an area where process execution and operator practices had a direct influence on performance, making it an ideal opportunity for Lean Six Sigma improvement without requiring major capital investment.

Measure: Building a reliable baseline

One of the most important findings emerged during the Measure phase.

Before improvements could be made, Elisa needed confidence in the measurement system itself. Her analysis revealed that data collection was highly dependent on operator behaviour and that a significant percentage of process events were not being recorded consistently.

Rather than rushing to implement solutions, Elisa followed Lean Six Sigma principles and first focused on understanding the measurement process. Through detailed data collection, measurement system analysis, and baseline performance assessment, she established a clear picture of current performance and identified significant variation in both process execution and data reliability.

This disciplined approach ensured that every improvement made later in the project would be based on facts rather than assumptions.

Analyse: Finding the vital few causes

Using the Fishbone diagram Cause-and-Effect matrix, Pareto Analysis, process observation, and statistical data reviews, Elisa systematically investigated the sources of variation.

The analysis revealed that a relatively small number of factors were responsible for the majority of the performance variation.

Key root causes included:

• A lack of standardised operating procedures
• Differences in operator working practices
• Inconsistent measurement adherence
• Production time pressures competing with measurement activities
• Unclear triggers for when measurements should be performed
• Product characteristics that influenced product recovery during barrel changes

Importantly, the data showed that the process itself was capable of achieving the desired performance. Many operators were already consistently delivering low-loss results. This indicated that the opportunity lay in improving consistency, standardisation, and adherence rather than redesigning the process entirely.

Improve: Turning analysis into action

After identifying the main causes of variation, Elisa focused on making practical improvements that could be easily integrated into daily operations.

One of the key improvements was simplifying and visualising the existing barrel change process. Rather than creating a completely new way of working, Elisa worked together with the operational teams to review the current process, remove unnecessary steps, and make the required actions clearer. The improved visual process made it easier for operators to follow the same approach, reducing differences between shifts and creating a more consistent way of working.

Elisa also focused on improving how residual product was recovered during barrel changes. By observing current practices and testing different approaches, she developed a simple visual standard that helped operators consistently recover more product. This reduced variation between shifts and helped minimise product losses.

Training was an important part of ensuring the improvements were successfully adopted. Elisa delivered practical shopfloor training sessions, using simple visual materials to explain what was changing, why the changes were important, and how the new approach should be followed.

Finally, improved data collection and enhanced Power BI dashboards gave the team real-time visibility of process performance. Instead of relying on manual checks, Team Leaders and Process Engineers can now quickly see whether the process is performing as expected. If performance falls outside the agreed standards, the dashboards immediately highlight the issue, allowing the team to investigate the cause and take corrective action before problems become more significant.

Control: Embedding the improvements

Many projects achieve short-term improvements. The real challenge is ensuring those gains are sustained.

Elisa placed significant emphasis on the Control phase, embedding the new standards into existing operational systems and routines.

Performance is now monitored through structured dashboards, routine reviews, visual standards, adherence checks, and clearly assigned ownership within the operational team.

Weekly reviews ensure performance remains visible, while Team Leaders and Process Engineers have clear responsibility for monitoring adherence and responding to any deviations. By building the controls into existing management systems, Elisa ensured that the improvements would continue long after the project was completed.

Delivering significant results

The project delivered measurable improvements across multiple performance indicators.

Average losses were reduced by approximately 15%, while process variation was reduced by around 50%. Process capability improved significantly, and measurement adherence increased substantially, creating a much more reliable foundation for future decision-making and continuous improvement efforts.

The project generated a significant financial benefit, delivering a ROI of around five times the course investment. Perhaps even more importantly, these results were achieved without any capital expenditure. The improvements were realised through better process design, standardisation, improved visibility, and stronger engagement from frontline teams.

In addition to the direct savings, the organisation now benefits from improved process control, more reliable performance data, increased operational discipline, and a stronger culture of continuous improvement.

Would you like to learn more about the potential benefits and ROI of Lean Six Sigma projects? We recently published an article analysing the ROI of 200 Green Belt and Black Belt projects completed by our delegates.

The value of expert coaching

Completing a Green Belt project while balancing daily operational responsibilities can be challenging, which is why coaching plays an important role in the learning journey.

Throughout the programme, Elisa worked closely with Dean Arnold, Master Black Belt at The Lean Six Sigma Company, who provided guidance and support throughout each stage of the DMAIC methodology, helping her successfully apply the Lean Six Sigma approach in practice.

Reflecting on her experience, Elisa was particularly grateful for the opportunity to learn from an expert with such deep expertise.

“The Green Belt training itself was extremely useful and gave me a clear structure to approach the project step by step. Having Dean Arnold, , as my coach also gave me access to strong technical expertise when needed. The course helped me better understand how to apply the DMAIC methodology in a practical way, from defining the problem and building a reliable baseline to analysing root causes and sustaining the improvements. It gave me valuable tools and confidence that I was able to apply directly in a real operational environment.”

Building capability for the future

For the organisation, the value of the project extends far beyond the immediate operational improvements.

According to Ron Schumacher, Continuous Improvement Manager at the company, the project represents exactly the type of outcome the organisation hoped to achieve through its investment in Lean Six Sigma capability development.

“I am extremely proud of the development Elisa has gone through during her Green Belt journey. She has successfully delivered a project with measurable business benefits, but equally importantly she has significantly developed her professional skills, analytical capabilities, and confidence in leading improvement initiatives.”

“One of the objectives of the Green Belt programme is not only to improve processes, but also to strengthen our internal Continuous Improvement capability. Elisa’s project demonstrates exactly that. We now have another colleague who can independently apply Lean Six Sigma methods, lead data-driven improvements, and support our continuous improvement culture.”

“The project results directly contributed to the strategic objectives of the Ashford manufacturing site by reducing waste, improving process control, increasing operational discipline, and strengthening data-driven decision-making. It is a great example of how personal development and business performance improvement can go hand in hand.’’

Congratulations Elisa

We would like to congratulate Elisa Iribarren on successfully completing her Green Belt certification and delivering an outstanding improvement project for the business.

Her project demonstrates the power of combining structured problem solving, data-driven decision making, effective stakeholder engagement, and expert coaching to deliver sustainable business results.

We look forward to following Elisa’s continued Lean Six Sigma journey and seeing the impact she creates in the years ahead.

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