What is Six Sigma Safety

Updated: Jun 25, 2019

Those of you in the safety world that also look after quality for your respective companies will likely be familiar with Lean Six Sigma if only vaguely. The methodology, which is actually two separate approaches (Lean to become more efficient and reduce waste, and Six Sigma to reduce errors which lead to defects) is intended to improved quality. It has been popular since the 1980’s when Motorola helped develop it but really became main stream when General Electric started using Six Sigma under the direction of CEO Jack Welch.

Six Sigma’s Application to Safety

Applying Lean principles to safety processes can streamline documentation, improve emergency response times, and help give ownership of safety to the workforce. However it is through Six Sigma and the elimination of errors within a safety management system (SMS) that real improvement in safety begins to occur. Assuming a mature and robust SMS is already in place, by removing the chance for error within that SMS, the defects (incidents and near misses) are eliminated. Instead of addressing potential faults in your safety program only after an incident has occurred and the investigation has identified the root causes, Six Sigma Safety addresses the potential faults in a proactive way.

The best approach is to dig out and eliminate problems where they are assumed not to exist – Shigeo Shingo


There are two main processes followed when using Six Sigma, DMADV and DMAIC. DMADV stands for Define, Measure, Analyze, Design, and Verify. DMADV is primarily used when developing a new process or product. DMAIC, the more widely known and utilized approach, stands for Define, Measure, Analyze, Improve, and Control. So unless you are starting from scratch, DMAIC is what safety professional will find most beneficial.

  • Define – This phase is used to identify the goals of the project, the scope, any key measures that will be used, and discuss the key business issues. A problem statement and business case rationale may be developed here.

  • Measure – In this phase a summary of the currents state of affairs is the objective. Often times the metrics you seek for Six Sigma Safety projects don’t exist. Although developing new metrics is time consuming and labor intensive, ensuring you are measuring the correct processes is vitally important to the success of your project.

  • Analyze – During this phase you will be analyzing the gaps between the current performance and the target performance. It is also during this phase where an explanation of any possible sources of variation will be identified. Unfortunately, many projects fail because too little time is spent on this phase in favor of jumping to the next phase. If data analysis is not your thing, it may be a good idea to bring someone in who has experience with Six Sigma to assist.

  • Improve – Like I mentioned above, it is often tempting to jump right to this phase. However the improvement phase should only occur once a complete understanding is achieved during the measure and analysis phases. Once that is secure, recommendations for improvement to the system can be developed with particular attention given to the practicality of the actions and whether or not the outcome will affect the target performance levels in the right way.

  • Control – Whether it be poke-yoke items, tracking systems, or standardizing of work processes, developing a system to ensure ongoing change management and control is important to the continuous improvement roots of the Six Sigma methodology. A good analogy for this is if you imagine your spring cleaning each year. Because most households don’t have a control phase built into their cleaning ritual each spring, they find themselves in the same situation year after year, a dirty house. With the creation of tools that maintained their clean home, spring cleaning would only be done once!

Data Based Decision Making

Unlike corrective actions that are by their very name reactive, the improvements that arise from Six Sigma Safety are proactive. Additionally, these improvements will be based on sound data from studies into various aspects of the SMS instead of what may have been an isolated incident or gut reactions. By using the DMAIC approach to gather information, not unlike the scientific method we all learn about in school, and then applying some simple statistical analysis, we are able to make data based decisions that have a better chance of moving our current state to the one we desire.

Bringing Six Sigma Safety to Your Workplace

Implementing a Six Sigma Safety mindset in your company will not be easy. It will however be well worth the effort when the SMS produces lower incident rates. It is also often easier to secure the required resources to implement change when the rationale for the change is evidence based opposed to something “we just ought to do”.

  1. How are changes to the SMS decided upon where you work?

  2. Do you have experience implementing Six Sigma in your workplace? Was it meant to serve a safety function?

  3. What do you think would be the biggest challenges to implementing a Six Sigma Safety mindset at your workplace?