Ergonomic workstation design

Engineers and designers play a key role in workplace ergonomics and the prevention of musculoskeletal disorders, which significantly impact organizational health and productivity.

Below is a summary of our ergonomics training for machine and equipment designers, followed by a mini video course led by Olivier Girard. This module forms part of the ErgOHListic Method and is also available as a 4-part webinar (40 minutes each).

Ergonomic hazards

To prevent musculoskeletal pain and physical discomfort, four risk factors must be controlled:

• Posture
• Activity
• Duration (or frequency)
• Stress

Your role as an engineer is to ensure that among the first three factors, no more than one occurs at the same time.

• No bad posture for a long time
• No carrying of loads at high frequency
• No carrying of loads in poor postures

It is not recommended to work alone on the design of a piece of equipment: the employees know the job and the production constraints better than anyone else, and the HSE specialists will help you determine the health risks.

 

Ergonomic design process

Below is the process to design a new working zone (industry or else).

Optimizing working posture

To choose the best posture at the workplace, two criteria must be analysed: the task to be performed and the organisation of the working day.

Ergonomics aims on the one hand to adapt the posture to the task:

• standing: posture for exerting force (carrying more than 6kg), for handling large parts, for making large movements, or for short cycle times;
• sit-stand: posture for light to medium work (3-6kg), without handling large objects or moving around;
• sitting: for long cycle times (more than 5 min), with little force, for handling small objects, for small movements, or for precision work.

In addition, the employees’ day must take into account their need for postural variation: one should neither stand nor sit all day.

Either employees can switch between workstations with different biomechanical profiles, or each workstation should be adjustable to allow sitting and standing work, if the activity allows it.

The best solution can be found in consultation with the management, which is responsible for the day-to-day organisation of the work.

Which support for posture?

To stabilise the employee (i.e. reduce the static load on the body), ensure that

• the feet are flat on the ground,
• the heels are right below the knees (especially when sitting: watch out for footrests far in front!),
• the pelvis is supported by a height-adjustable lumbar support (sitting and semi-standing).

Only use footrests or platforms when strictly necessary: use height-adjustable workstations so that everyone can work comfortably regardless of their height. The extra cost is minimal compared to the benefits over the depreciation period of the workstation…

Grip zones and visual field

Then, place the work in the comfort zone for the hands and indicators in the preferred field of view.

How to protect the joints

Finally, zoom in on each joint to ensure that they are not being used in extreme positions.

Activities involving strength or repetitive movements should be performed around neutral postures, in which the muscles have maximum power.

The area of maximum strength for load bearing is around the pelvis; the weight limits are shown below (decreasing with age and frequency of the task).

Workers’ participation

Employees know their work better than anyone else: involve them in every phase of the development process, and don’t hesitate to make several mockups.

Integrating your workers’ input is essential for effective ergonomics implementation. Their body awareness and practical experience are irreplaceable when aiming for long-term pain prevention.

 

To go further

• Dined anthropometric database (TU Delft, The Netherlands)

Need an ergonomics engineer?

These guidelines represent just a fraction of the ErgOHListic Method’s approach to occupational health. If you’re interested in applying these principles to your own teams or projects, fill out the form at the bottom of this page to request a meeting with Olivier Girard.