What Is Lean Ergonomics (And Why Does It Matter?)
Lean systems can help your workplace take a more proactive approach to preventing ergonomic injuries.
The value of integrated management systems is well understood in theory but often poorly implemented in practice. The Safety Manager and Quality Managers sit back to back and manage their discrete systems exclusively from one another.
In fact, my own thinking is so compartmentalized that when I first heard the term “lean ergonomics,” my safety mind went to an image of a leaning procedure that prevents injuries.
It’s… nothing like that.
What Is Lean Ergonomics, Then?
"Lean" refers to a production method modeled after Toyota's operation systems from the mid-twentieth century until the 80s. It incorporates management ideas from Frederick Taylor and Henry Ford – familiar mainstays in any Intro to Business course.
(Learn more about Creating a Lean Safety Culture: Does 5S Need a Sixth S?)
Ergonomics considers the human factors in processes in order to influence the engineering and design of equipment and procedures with the overall aim of “fitting the task to the person.” As part of a comprehensive health and safety program, it can be a means of reducing repetitive stress injuries, problems resulting from awkward posture, and other frequent lost-time contributors.
Pairing lean systems and ergonomics may not be totally intuitive, but that's what makes it an innovative approach.
Traditional thinking in ergonomics applies a very limited scope. It typically only deals with issues that are potential contributors to injuries. Implementing lean thinking in ergonomics means thinking about every human interaction with a process and examining the waste and resulting loss in both quality and safety simultaneously.
The Lean Approach to Ergonomics
Lean systems view ergonomic injuries as a process inefficiency more than a safety and health issue. Consequently, this approach to dealing with ergonomics involves a higher-level, holistic insight. Rather than an expensive, specific, and esoteric program aimed at reducing possible injuries, ergonomic programs are viewed as a way of reducing inefficiency, thus increasing production. Ergonomics, then, becomes an integrated part of the overall quality management system.
Lean philosophy aims at reducing three categories of waste in processes. By their Japanese terms, they are called:
- Muda (unproductive activities)
- Mura (unevenness or inconsistency)
- Muri (overburden, unreasonableness, or absurdity)
While most operational processes would consider muri in running their machinery (push a machine too hard and it will break down frequently), it fails to apply the same thinking to human workers. Lean ergonomics extends the notion of functional assets to people, and aims to apply the same approaches. Excessive actions and repetitive movements and other sources of process waste are targeted, and many can be reduced with a proper lean approach right from planning stages.
(Learn about Implementing a Safety Kaizen Program: Incorporating Lean Principles Is Easier Than You Think.)
Quality systems and ergonomics are more than a marriage of convenience; they are necessarily intertwined. A functional but incomplete implementation of lean that overlooks ergonomics may in fact increase the incidence of injuries and conditions in the short term. Lean aims to increase productivity by reducing waste, which can mean fewer breaks and higher demand on employees. So while muda (unproductive activity) is targeted, the result can be increase in muri (overburden). Both are sources of waste, and the latter is a key source of ergonomic issues.
If ergonomic risk factors and process efficiency are considered together, lean systems may view production deficiencies as a top-down indicator of ergonomic issues. Undesirable delays or other kinds of process “waste” can act as a prompt to investigate ergonomics, where a traditional investigation approaches basically relied on injury rates and intuition. These approaches could establish links between ergonomic issues and health and safety problems (like incidences of musculoskeletal disorders) after the fact. Lean ergonomics, on the other hand, offers an opportunity to capture and control ergonomic issues before they result in lost time or other losses.
(Learn the Top 5 Ways to End Up with a Musculoskeletal Disorder.)
Consider a manufacturing process in which a worker transports a widget from machine to a cooling table located 10 feet away. Maybe the worker repeats the step numerous times in a day, each time taking an almost negligible few seconds of time. In a lean environment, when numerous inefficiencies subtly compound, the resulting production delays or missed targets should trigger a survey of relevant processes that includes ergonomics. It may find that moving the cooling table is possible, and into such a position as to not require pitching, twisting, and reaching. The task is now made less cumbersome, and eliminates a number of steps and cumulative time wasted per day.
The distinction from conventional ergonomics is mainly in the fact that these sources of waste may take long time to surface or may never make themselves apparent in injuries and lost time. Their indicators are hiding in the quality sphere, not in safety. And lean systems strive to erase those boundaries.