Ergonomics and Lean Thinking: The Golden Zone Meets Efficiency and Health

Ergonomics as a Lever for the Lean Thinking Approach

The Lean Thinking It is no longer just a set of practical techniques, but a true business philosophy go back to maximize the value for the client, minimizing all forms of waste. Often, when discussing lean processes, the focus is on flow, pull e takt time, but there's a risk of neglecting the most valuable resource: human contribution. This is where the’ergonomics Workstations come essential investment comes into play.

An ergonomically optimized workstation doesn't just prevent injuries or occupational illnesses; it's a catalyst for greater efficiency, Quality and motivation. The goal is simple yet profound: to enable people to work without wasting physical or cognitive resources, transforming the operating environment into active support for productivity. This integrated approach, which merges the pursuit of production optimization with attention to physical well-being, is the key to value chains more resilient and efficient, typical of a path of continuous improvement and of Lean World Class®.

The economic impact of ergonomic inefficiency on Lean manufacturing

Poorly designed workstations incur exorbitant and often underestimated costs, which translate into tangible figures on company balance sheets. The data is clear: a significant portion of work absences, reaching nearly a quarter of the total in some sectors, is directly attributable to musculoskeletal problems. These are not mere temporary discomforts, but represent production flow interruptions, costs for replacing employees, and ultimately, a loss of competitiveness.

The’Integration between Ergonomics and Lean Thinking translates to a economic savings measurable. Just think: Reduction of absences for musculoskeletal problems, process efficiency, reduction of non-value-added activities, workplace safety, product quality thanks to a robust and error-proof process, development of skills on products and equipment.

The concept of the Golden Zone: the optimal grip area (one of the Lean tools indirect

The fundamental principle for organizing an efficient workstation consists of defining and applying the Golden Zone (or optimal grip area). This area does not represent a fixed, delimited zone, but rather an ideal three-dimensional space immediately surrounding the operator, in which all tools, components, and operating elements can be reached and manipulated with minimal effort and movement.

The grip area and the movement

Workspace design must minimize any unnecessary movement. Trunk rotations and excessive shoulder movements, especially under load, should be avoided. The Golden Zone is, in fact, defined by Anatomical and physiological range of motion of the operator, ensuring that essential work elements are accessible without strenuous reaching, twisting, or bending.

Applying the concept of Optimal Grip Area correctly in a nut shell Lean means:

• Reduce the mstop at the stopEvery time the operator reaches or leans unnecessarily, it causes a waste (Changethat does not add value to the product. The Golden Zone combats this waste directly.
• Increase cyclic efficiency: By reducing the time required to pick up and place objects, the overall cycle time is reduced, improving the production flow.
• Prevent fatigueeasy access prevents muscle fatigue, which leads to a drop in performance and a worsening of the Quality.

Working height (the vertical dimension of the Golden Zone)

Another determining factor is the’Optimal working height, which constitutes the vertical dimension of the Golden Zone. This height must be calculated based on two key parameters: the worker's stature and the Type of business turning point.

• The safe intervalIn general, the optimal vertical workspace should be between 800 mm and 1500 mm relative to the floor.
• Things to avoidIt is essential to avoid any activity that requires working above heart level. In these positions, blood circulation slows down, reducing oxygen supply to the muscles and causing a drop in performance. Similarly, activities that require operating below 800 mm They involve excessive and unnecessary bending, tiring the operator. The ideally positioned workspace is therefore below heart level, promoting adequate oxygen supply and an increase in performance.

For non-continuous activities performed while sitting or standing, the optimal average working height is approximately 1125 mm, but this value should always be considered a starting point for personalization and’Process optimization.

Personalization and dynamism: ergonomic flexibility as Lean tool

One of the fundamental principles of proper ergonomic design is adaptability. Since the workforce is made up of individuals with different statures and physical characteristics, an optimal workstation must be adjustable. This approach to ergonomics and lean thinking aligns with the Lean principle of respect for people and allows for continuous improvement of working conditions.

The calibration of work tools

The Golden Zone and working height must be customized for each operator, a process that requires adjusting several tools work:

1. Chairs and footrestsmust be adjusted so that the thigh and calf form a right angle (90°). Similarly, the upper arm and forearm should maintain an angle of around 90° during the activity. Correct posture is essential to support the performance.
2. Shelves and storage unitsthe inclination and height of the shelves holding the materials must be adjusted to create direct grip spaces and reduce the useless movements.For heavy components, elevators and lifting systems should be used.
3. Visual aidsInformation panels or monitors should be mounted at eye level to eliminate unnecessary head movements.

The correct adjustment of the desk, chair, supports, and containers is not a one-time operation, but a dynamic process must be regularly checked to cope with staff turnover and process or product changes.

The importance of dynamic activity in production flow

Ergonomics is not limited to static posture. The human body is designed for movement, and prolonged static activity (such as sitting or standing excessively without variation) impairs blood circulation and oxygen supply to the muscles, leading to a deterioration in work performance.

The Lean approach involves the implementation of dynamic activities and promoting frequent changes in posture and different physical stresses. A complementary strategy is Job rotation, allowing physical effort to be distributed across different muscle groups, reducing the load on individual body parts and improving overall efficiency.

Ergonomics, Vision, and Quality (Poka-Yoke)

A further fundamental aspect of ergonomic design concerns the visual environment, which significantly impacts work quality. Adequate visual ergonomics effectively supports the strategy Mistake-proofing (error-proof), minimizing the probability of defects due to fatigue or distraction.

• Ideal lighting: Proper lighting is essential to prevent premature fatigue, improve concentration, and reduce the risk of errors. It is necessary to avoid strong contrasts, glare, and reflections that can strain eyesight and compromise the operator's attention during work activities.
• Optimized field of vision: It is essential to minimize unnecessary head and eye movements. In addition, keeping objects and inspection points at a constant distance from the operator's view eliminates the need for continuous refocusing, a process that can quickly fatigue the eyes and slow down work.

Improved visual conditions allow the operator to focus on the added value of the activity, minimizing waste. The adoption of these continuous improvement tools is a hallmark of a Lean World Class® approach.

Ergonomics as the foundation of sustainable performance

The’Integration of Ergonomics and Lean Thinking represents a forward-thinking and strategic business strategy. The implementation of Principles of the Golden Zone (or Optimal Grip Area) It is not limited to mere compliance with regulations, but rather constitutes the adoption of an operational model in which the health and well-being of human resources are directly correlated with productive efficiency and effectiveness.

Effective ergonomics is not only an act of respect for people, but also a true driver of business growth:

• Productivity Increase: The reduction of superfluous movements and fatigue allows for higher and more consistent performance over time.
• Quality improvement Less fatigued and more focused operators significantly reduce the margin for error.
• Waste reduction (Muda): The time and costs associated with absences, injuries, and unnecessary movements are drastically reduced.

The Lean approach requires optimization of each stage of the value chain. Ensuring workplaces are designed to accommodate human capabilities and limitations is the most fundamental and, in the long run, the most profitable optimization an organization can implement. Placing people at the center of the business strategy, providing them with a dynamic and personalized work environment, represents the authentic key to lean, integrated, and above all, competitive production, oriented towards achieving Lean World Class®.