From The Ergoweb® Learning Center

You Can’t Achieve Six Sigma Without Ergonomics (reprint)

This article is reprinted with permission from The Ergonomics Report™, where it originally appeared on November 1, 2002.

Update: Contributors Ben Zavitz and Mike Wynn have pursued new career opportunities since this article was published over 10 years ago. Ben is now an Ergonomist at General Dynamics Bath Iron Works, and Mike is a Director at Advanced Purchasing Dynamics.

Any team presented with a big project that seemingly becomes more and more complex might groan at the prospect of putting ergonomics into the mix. But with a Six Sigma project, ergonomics neither conflicts with nor takes resources from other management or process systems that may already be implemented within a company.  Instead it adds to the proper execution of the Six Sigma process.

“Incorporating ergonomics into Lean/Six Sigma creates a win-win situation for both production and safety,” says Ben Zavitz, an Ergonomist for Boeing’s Manufacturing Research and Development in Auburn, Washington. “Employees experience less discomfort and fatigue which results in improved productivity and quality.  However, in the beginning stages, people may be hesitant to address ergonomic issues, as they believe ergonomics may slow the process down or cost too much money. [But] focusing on practical simple solutions early on can help gain acceptance and approval of the need and benefits of ergonomics in a Lean/Six Sigma System,” Zavitz says.

“Ergonomics parallels Lean/Six Sigma — both have their origins in Industrial Engineering. One is concerned with manufacturing efficiency and the other with human efficiency,” says Zavitz who has first hand insight from his work at Boeing and through his presentations on the subject at conferences in the U.S. and Canada. “We should strive to make the employee’s job as easy as possible,” Zavitz says, “and get away from trying to define what is an acceptable or unacceptable magnitude and/or duration for a given ergonomic risk factor.  By addressing employee ergonomic concerns during Lean/Six Sigma activities, Boeing has been able to show a significant improvement in safety, productivity and quality.”

Ergonomics uses knowledge about human capabilities, limitations, and characteristics, to design work processes.  Each of these are areas that can lead to greater efficiency and quality while minimizing the risk of developing, for example, costly musculoskeletal disorders (MSDs).

Six Sigma is a system that aims to improve customer satisfaction, reduce cycle times, and reduce product defects.  This was also the goal of some TQM programs that died a slow and quiet death at many companies in the 1980s.  But Six Sigma has new twists, including the martial arts “belt” system to designate a person’s level of training (don’t be surprised if someone at your company asks you if you’re a green belt, or has a celebration after reaching the coveted black belt designation). These belts have nothing to do with high kicks or breaking boards, but they do reflect the level of expertise a person has with the Six Sigma program.

Achieving true Six Sigma in an organization is a hefty goal. As a statistical term, “Six Sigma” means that a process or product has almost zero defects.

When a company implements a Six Sigma program, they want a systematic approach to address and correct quality issues. Often, poor quality or slow production can be linked to poor ergonomics. With a knowledge base in ergonomics, the team can successfully address the problem, and ultimately produce a better product that satisfies customers, but without adding more to anyone’s already-full plate.

In its strive for near-perfection, Six Sigma involves five components  — Defining the goals, Measuring the process/problem, Analyzing the cause, Improving the process, Controlling the future process (note — this is the DMAIC approach; a DMADV approach — define, measure, analyze, design and verify, also exists). Mike Wynn, Vice President of Humantech, offers this case study where Six Sigma and ergonomics worked together to solve an office worker discomfort problem:

In 1999, a U.S. Federal agency discovered growing challenges related to ergonomics with their office-based population that was ultimately affecting their customers’ expectations. The agency’s Occupational Safety and Health Manager submitted a proposal to conduct an ergonomics assessment of headquarter operations.

Define: The following goals were identified:

  • Respond in a timely manner to individual discomfort issues.
  • Provide rapid improvement to individuals as their workstations are assessed.
  • Define furniture and equipment needs for the next budget cycle.

Measure: The results of the detailed discomfort survey found that 15% of the population reported significant discomfort.  This data was further analyzed to identify the body parts that were most commonly cited for significant discomfort:

  • Lower back (8.2% of the population)
  • Neck (6.7%)
  • Right shoulder (6.0%)

Analyze: A survey method was used to identify workstation conditions contributing to discomfort. Scores showed that 14% of the population were a high priority. Within this high priority group, inadequate keyboard supports and poor seating were identified as root causes.

Improve: The solution to poor seating involved procuring and providing seating that meets current guidelines for computer workstations. The solution to inadequate keyboard support was more complicated due to the variety of furniture systems.  After thorough investigation, two classes of workstations were derived with an appropriate improvement for each. The majority of high priority individuals were provided with new keyboard trays, while a number of individuals had their work surfaces retrofitted to provide adequate space and height adjustability.

Control: The agency used the information derived from the survey to establish workstation typicals for installation upon site relocation.  These workstation typicals address important elements including workstation layout, keyboard support, seating and lighting.

“Whether you are an ergonomics practitioner or a Lean facilitator, incorporating ergonomics . . . is a win-win situation for both parties,” says Boeing’s Zavitz.  “[At Boeing] reducing employee exposure to awkward postures and forceful exertions has resulted in both productivity and quality improvements. Our Lean Facilitators are now realizing that many of our production bottlenecks, quality and re-work issues may be caused by less than perfect ergonomic conditions.  In one of our sub-assembly areas we eliminated employee back flexion, through the use of a height adjustable trunnion, which resulted in a 25% reduction in cycle time,” says Zavitz.

In the end, implementing Six Sigma is the challenge; putting ergonomics into the mix makes the system work for itself — fluidly and fully, effectively, productively and efficiently.  The success of any business is ultimately dependent upon the humans who make it work. Without adding ergonomics into the equation, the results can’t total up to Six Sigma.