If you’re the kind of engineer who is always looking to fine-tune your operations and get to the heart of any issue, you may already be familiar with Six Sigma. But if you’re not, you will certainly want to know more about this methodological approach to continuous improvement for your shop floor.  

Learn How Breiner Helped One of the Biggest Auto Manufacturers in the World

Ever wonder why defects or errors pop up in your process, seemingly out of nowhere? The Six Sigma method will help you and your shop identify the root cause of these problems, help you minimize these errors, and keep your customers happy. The Six Sigma approach will make you a better leader with a shop where continual improvement is fostered. Let’s take a look! 

An Overview of Six Sigma

Before we dive into Six Sigma as a root cause analysis tool, let’s take a moment to understand what Six Sigma is. Six Sigma is a data-driven process improvement methodology designed to reduce process variations and minimize errors. 

By setting a target of 3.4 defects for every one million defect-free products —an accuracy rate of 99.99966%— Six Sigma pushes organizations to strive for excellence. 

The Principles of Six Sigma

Perhaps it’s obvious, but there are six key principles of Six Sigma. These principles serve as the foundation for process improvement and drive organizations towards optimal performance. They are: 

1. Focus is always on the customer 

In Six Sigma, the customer takes center stage. Understanding the customer’s needs and expectations is crucial in delivering quality products and services. 

By aligning processes with customer requirements, organizations ensure customer satisfaction and loyalty. 

2. Improvement is a continuous process 

Six Sigma is not a one-time fix: it is a journey of continuous improvement. It encourages organizations to always seek and identify new improvement opportunities. 

As soon as one process reaches the Six Sigma standard of accuracy, it’s time to identify the next one and create an improvement plan. 

A shop leader shows apprentices a CNC machine and program, demonstrating the Six Sigma principle of leadership.

The Six Sigma methodology uniquely improves leadership skills on the shop floor.

3. Reducing process variation is critical 

Errors are more likely to occur when different team members or teams perform given processes differently. 

The Six Sigma approach standardizes processes across individuals and teams to reduce deviations from the target. By minimizing process variations, organizations achieve consistent and reliable results

4. Eliminating waste enhances outcomes 

Inefficiencies and unnecessary steps hinder performance and increase the likelihood of errors. Six Sigma aims to identify and eliminate wasteful actions within organizational processes. 

Through streamlined processes, organizations save time, reduce errors and their associated costs, and improve overall efficiency. 

5. Leadership development for continued success 

Within Six Sigma, leadership development ensures the organization continues to succeed. Six Sigma develops leaders at all levels, fostering consistency throughout the organization, and empowering staff to embrace an improvement mindset. By investing in leadership development, businesses create a culture of continuous improvement and drive their teams towards exceptional performance. 

To facilitate effective leadership development within the Six Sigma framework, the methodology invokes a martial arts approach through a “belt” system. Each “belt” represents the level at which the person’s understands and has used the Six Sigma method. These categories are: 

White Belts 

White Belts are the entry-level participants in Six Sigma. Through a few hours of introductory training, they gain a foundational understanding of the approach and its core principles. 

While White Belts are not directly involved in projects, they serve as important contributors to the overall knowledge-sharing and improvement efforts within the organization. 

Yellow Belts 

Yellow Belts have a deeper understanding of Six Sigma principles and play a supporting role in process mapping and improvement initiatives. 

They contribute their knowledge and skills to identify opportunities for optimization and collaborate with Green and Black Belts to drive effective change. 

Green Belts 

The Green Belt represents a significant step forward in leadership development within the Six Sigma hierarchy. They have a Black Belt mentor who guides them in applying Six Sigma methodologies to their daily work. 

Green Belts actively utilize Six Sigma principles and tools, taking leadership roles in specific projects. Their expertise and understanding of process improvement contribute to driving positive change within their teams and across the organization. 

A man wearing a black belt, representing the level of Six Sigma mastery.

Do you have what it takes to don a Black Belt in Six Sigma?

Black Belts 

The Black Belt level signifies a high level of expertise and advanced knowledge in Six Sigma. Black Belts possess advanced team management skills and are well-versed in the intricacies of project tools and design processes. 

With their analytical prowess and mastery of software tools, Black Belts drive data-driven decision-making and conduct in-depth analysis to identify root causes and implement effective solutions. 

Master Black Belts 

At the highest level of leadership development in Six Sigma, we find the Master Black Belts. These individuals have the requisite knowledge and experience needed to manage Black and Green Belts effectively. 

Master Black Belts serve as mentors and trainers, assisting others in their Six Sigma journeys. They play a critical role in guiding teams through complex projects and providing expert consultation on particularly challenging initiatives. 

6. Define and control all processes 

To drive improvement, organization leaders need to understand the processes currently in place. Only then can you truly begin to address and correct shortcomings. 

By defining and controlling processes, organizations identify areas for improvement and measure the impact of those improvements. This helps ensure once the improvement has been reached, it remains within the Six Sigma level. 

Understanding Root Cause Analysis in Six Sigma 

Now, let’s explore the concept of root cause analysis and its role in Six Sigma. Root cause analysis identifies the causes of defects or errors within a process. It goes beyond addressing symptoms and focuses on addressing the root cause to prevent future occurrences. 

Root cause analysis helps organizations understand why defects or errors are happening and provides insights into how to eliminate them. By understanding the root cause, organizations can implement effective corrective actions and prevent recurrence. 

A man uses a coordinate measuring machine to verify the quality of a part, as part of Six Sigma quality control checks.

Six Sigma represents a constant push for shops to pursue perfection!

Root cause analysis in Six Sigma involves using various techniques such as the “Five Whys” and fishbone diagrams to investigate and analyze the causes of defects.

These techniques help teams identify patterns, assess process variables, and determine the impact of each potential cause. Armed with this information, organizations can make informed decisions and take targeted actions to improve performance. 

The Role of Root Cause Analysis in Defect Identification 

Root cause analysis is essential for pinpointing and eliminating defects in a process. It’s a vital component of DMAIC—Define, Measure, Analyze, Improve, Control—a structured approach that drives process improvement and defect reduction. 

Here’s how root cause analysis fits into each DMAIC phase: 


Identify and define the problem by asking probing questions and investigating the impact on performance. 


Gather accurate data to measure the current process performance and identify areas for improvement. 


Analyze data to identify the root cause of defects. 


Implement targeted solutions to address the root cause and achieve lasting improvements. 


Continuously monitor process metrics and implement measures to sustain the achieved improvements. 

Root cause analysis, integrated into DMAIC, offers a systematic approach to problem-solving, improving performance, and preventing recurring defects. 

Implementing Root Cause Analysis in Six Sigma 

Now that we understand the fundamentals of root cause analysis, let’s explore how organizations can effectively implement this powerful tool within the Six Sigma framework. Here are some tips for successful implementation: 

Data collection and analysis: 

Collecting and analyzing reliable data is essential for conducting an effective root cause analysis. Organizations should invest in data collection tools and ensure the accuracy and completeness of the data. 

Teamwork and collaboration: 

Root cause analysis is a team effort. Encourage collaboration among team members, involving individuals with different perspectives and expertise. By leveraging the collective knowledge and experience of the team, organizations can uncover insights and find innovative solutions. 

Two engineers collaborate on CAD software, demonstrating root cause analysis and Six Sigma.

Collaboration and teamwork are key to identifying and solving problems.

Focus on continuous learning: 

Root cause analysis is a continual learning process. Encourage a culture of learning and improvement within the organization. This is achieved through regular training, knowledge sharing sessions, and lessons learned exercises. 

By implementing these tips, organizations harness the power of root cause analysis to uncover the true reasons behind defects or errors. As a result, businesses make data-driven decisions to improve their processes. 

Get the Best Out of Your Organization with Breiner Innovative 

Root cause analysis is a critical tool in the Six Sigma toolbox, empowering organizations to identify and eliminate the underlying causes of defects or errors. By implementing this powerful technique, organizations achieve optimal performance, reduce waste, and deliver quality products and services. 

If you’re ready to unlock the potential of root cause analysis and take your process improvement efforts to the next level, Breiner Innovative is here to help. Our experienced team brings a wealth of knowledge and expertise to every project. Contact us today to learn more about our services and how we can assist you on your journey towards process excellence. 

Remember, when it comes to process improvement, the power of root cause analysis is in your hands. Embrace Six Sigma and let Breiner Innovative be your partner on the path to success! 

Common types of gasket materials. This helpful infographic takes a look at the most common types of gasket materials. Download your infographic here.