Lean Six Sigma (LSS) is a powerful methodology that helps organisations enhance efficiency, reduce waste, and improve overall quality. However, selecting the right training level—Yellow Belt or Green Belt—depends on an organisation’s specific needs and objectives.
This case study explores how a £250 million annual turnover medical nutrition company used Lean Six Sigma to optimise changeover times and how both Yellow Belt and Green Belt training played a role in the solution.
Related Article: Lean Six Sigma: Why Most 5S Programs Fail (And How to Make Yours a Game-Changer)
Lean Six Sigma Yellow Belt
The Yellow Belt program is designed for employees who will contribute to process improvement projects rather than lead them. This two-day course provides a foundational understanding of Lean Six Sigma principles, equipping team members with essential problem-solving skills. Key benefits include:
- Understanding Lean Six Sigma fundamentals and how they improve efficiency.
- Learning process mapping techniques to identify inefficiencies.
- Applying root cause analysis to pinpoint issues.
- Reducing waste using the Seven Wastes framework.
- Using the Effort-Benefit Prioritisation Matrix to target improvements.
- Supporting improvement projects within their teams.
Lean Six Sigma Green Belt
The Green Belt program is a five-day course designed for those who will lead Lean Six Sigma initiatives. Green Belt professionals take on more responsibility, driving measurable improvements across their organisation. Key outcomes include:
- Leading Lean Six Sigma projects to reduce defects, waste, and process variation.
- Applying statistical and data-driven problem-solving methods.
- Conducting value stream mapping and advanced process analysis.
- Managing stakeholders and change adoption for project success.
- Implementing long-term sustainable improvements in operations.
Case Study: Optimising Changeovers to Improve Capacity
The Challenge
A £250 million turnover business, supplying over 2,500 formulations of medical nutrition products globally, faced a major efficiency issue:
- The average line downtime for changeovers between product formulations was 49 minutes.
- In a typical week, changeovers accounted for up to 25% of total process capacity, leading to production delays and inefficiencies.
- Leadership sought to reduce average changeover time to 12 minutes to improve productivity and reduce costs.
The Lean Six Sigma Approach
To achieve the target, the company implemented a structured Lean Six Sigma improvement project based on the Single Minute Exchange of Dies (SMED) methodology.
Key steps included:
- Observing and recording the changeover process: One shift performed the changeover while the other shift observed, recorded time stamps, and captured video footage.
- Process mapping & analysis: The team created a swimlane process map, breaking down each step into value-adding and non-value-adding tasks.
- Eliminating inefficiencies: Tasks that could be completed before or after the downtime were moved out of the changeover process.
- Redistributing workload: Operator responsibilities were restructured to ensure everyone was fully active during changeover time.
- Iterative testing & refinement: The new process was tested, refined, and re-evaluated over a two-week period to ensure optimal efficiency.
The Results
- 81% reduction in changeover time—from an average of 49 minutes to just 10 minutes.
- Allowed for smaller batch production, significantly reducing inventory costs and storage risks.
- Improved on-time delivery performance, as less reliance on long-term forecasts was needed.
- The same SMED methodology was later applied to reduce a 5.5-hour line clean to 2 hours and a 10-hour clean to 4 hours.
Which Lean Six Sigma Belt Did They Need?
Lean Six Sigma Yellow Belt
The Yellow Belt is ideal for frontline employees, operators, and team supervisors who are involved in improvement initiatives but do not lead projects.
At the medical nutrition company, operators and frontline staff benefited from Yellow Belt training, allowing them to actively contribute to the changeover optimisation project by identifying waste and inefficiencies in their workflow.
Lean Six Sigma Green Belt
The Green Belt is designed for those who lead Lean Six Sigma projects and manage improvement initiatives.
At this company, supervisors, engineers, and process managers used Green Belt training to lead the changeover reduction initiative, analyse process data, and implement a sustainable, standardised approach across all production lines.
Final Decision: A Dual Approach for Maximum Impact
By investing in both Yellow Belt and Green Belt training, the medical nutrition company achieved an 81% reduction in changeover time, unlocking significant capacity improvements without requiring additional investment.
This dual training approach ensured:
- Yellow Belt staff played an active role in day-to-day improvements.
- Green Belt leaders guided structured projects for long-term success.
Choosing the Right Belt for Your Organisation
If your organisation is considering Lean Six Sigma training, ask:
- Do you need employees to contribute to improvements but not lead projects? Choose Yellow Belt.
- Do you need professionals to lead and implement structured process changes? Choose Green Belt.
- Would a combination of both levels help create a culture of continuous improvement? → A blended approach may be the best strategy.
If you’re ready to go beyond the basics and harness the full potential of 5S, our Lean Six Sigma courses will guide you through practical strategies to implement and sustain 5S for lasting impact. Learn how to transform your workplace and drive measurable business results with Lean methodologies.
To explore training options, check out the Yellow Belt and Green Belt courses.
Pam Luo