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What is 6S Lean — and How Can It Improve Your Operations?

To manage supply chain challenges and ensure regulatory compliance, lean manufacturing has become commonplace for organizations. The approach isn’t new — American industrialists of early 20th-century law lean processes that focused on reducing waste and improving efficiency as a way to increase overall value.

The original 5S methodology, meanwhile, emerged as a companion to lean management thanks to Sakichi Toyoda, founder of the Toyota production system and often called the “father of the Japanese industrial revolution.” With five simple, alliterative steps, 5S made it possible to further improve production while driving increased efficiency with a focus on continuous improvement. 6S lean takes things a step further by adding a 6th S”: Safety.

What is 6S Lean?

6S lean manufacturing combines the five key tenants of 5S — sort, straighten, shine, standardize, and sustain — with safety. The goal of 6S is to ensure that safety is a part of all lean manufacturing processes from end to end, in turn reducing the risk of accidents and limiting the amount of production downtime.

The 6S framework is often imagined as a circle with the five core tenants around the edge and safety in the middle. While some critics of the 6S approach argue that safety should simply be another “step” in the process, the center position of safety in 6S lean speaks to its role across all operations from start to finish.

What is 6S Lean — and How Can It Improve Your Operations?

Key Components of the 6S Lean Framework

As noted above, there are six key components of the 6S methodology:

Sort (Seiri)

Sort focuses on reducing clutter in work environments by removing unnecessary items to improve overall efficiency. Items are often “tagged” by the color — green-tagged items stay, red-tagged items are immediately removed and yellow-tagged items are stored for later use.

Straighten (Seiton)

Straighten (also called set in order) speaks to organizing green-tagged work items within workspaces such that they’re easy to retrieve, use, and put away. By creating a systematic approach to production line processes, companies can increase accessibility and boost overall efficiency with an organized workplace.

Shine (Seiso)

Cleaning is the priority in this 6S component. From basic clean-up of tools and equipment around the work area to maintain a “pleasant” appearance, Shine is all about preventing problems by reducing the risk of sudden tool or machine failures. This component also speaks to building proactive and preventative processes that help workspaces stay clean over the long term.

Standardize (Seiketsu)

Standardization combines the work of the first three components to identify best practices and develop policies and work processes that support these practices over time. Standardization may include a written code of conduct, on-site visual reminders such as signs or posters, and regular site inspections.

Sustain (Shitsuke)

Sustain focuses on transitioning a 6s program from one-time practice to intrinsic application. This requires continual monitoring and evaluation until processes become second nature.


Safety ties all five S’s together by identifying possible hazards during each step of the process and developing methods to eliminate the hazards and keep workers safe — and productive.

Worth noting? 6S lean is sometimes called 6S lean six sigma, which refers to the application of statistical processes to ensure “six sigma quality”. In practice, six sigma quality focuses on creating processes that deviate as little as possible from ideal operational outcomes.

Why It Matters for Your Organization

Applying the 6S system framework to your organization can help drive two key outcomes: Speed and safety. Speed stems from the application of 5S processes — if production line stations are sorted, straightened, shined, and standardized and these ideals are maintained, overall efficiency increases even as waste decreases, in turn leading to faster production processes with no decrease in quality.

Adding the additional “S” of workplace safety, meanwhile, helps ensure that the focus of every step in the 5S circle is underpinned by safety. Consider the “straighten” phase of 5S. While establishing systematic ways of storing and retrieving tools and items offers benefits for efficiency, safety considers how this organization may impact employees — are certain tools or equipment suddenly out of reach? Will new processes require staff to sit, stand or turn in odd ways that could have negative impacts over time? By incorporating safety, companies can combine the health of the business with the health of individuals to benefit both.

30+ Audit and inspection checklists free for download.

How Certainty Software Can Help

To deliver on the potential of 6S lean, organizations require frameworks that support the details and documentation necessary to capture and compare operational data. For example, if specific processes aren’t working as intended — if they’re putting workers at risk or resulting in additional waste — companies need streamlined ways to record what’s wrong and create a solution. 6S lean software offers a way to centralize and streamline the implementation of this process.

As a result, robust software tools for 6S lean implementation are critical. Paired with in-depth evaluation criteria along with lean 6S checklists and templates, companies can pinpoint where processes aren’t living up to 6S expectations and make data-driven changes that benefit staff, stakeholders, and customers.

Ready to make the shift to 6S? Stay lean with Certainty Software.

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