More and more sedentary, we spend more and more time on a computer during the day, both at work and in our personal lives.
If new technologies have become unavoidable, computer work involves some health risks, both mental and physical. How to optimize ergonomics to work in good conditions? Discover our guide to good practices to adopt now!
Staying in front of a screen for several hours without taking regular breaks or with sufficient distance can cause injury. visual fatigue and discomfort, as we blink less often. Visual fatigue triggers manifestations of various types: localized redness, dry eyes, headaches, blurred vision, etc., which disappear after stopping exposure to screens, but which can return more or less chronically if good practices are not implemented.
The eye disorders can be both triggered by sensitivity factors (blue light , age, existing vision problems, etc.) but also by ergonomic factors linked, for example, to a too short distance from the screen, unsuitable lighting or even a bad placement of the desk which induce reflections on the screen and disturb the vision.
Very common when working on a computer, TMS (musculoskeletal disorders) are characterized by tension, numbness, pain in the muscles and tendons of the neck and cervical, back, shoulders, wrists and hands.
The appearance of MSDs is favored by a number of factors: unsuitable work posture, torsion of the back or neck for consultation and transcription of documents, unsuitable and badly adjusted furniture, etc. Stress and performing repetitive tasks also lead to a higher risk of developing MSDs.
In addition to physical health, the screen work can also cause stress because of the tasks performed or inadequate management. Overtime, pressure, a heavy work environment, work content unsuited to the skills and aspirations of employees promote a state of stress, which, if it is not contained, can lead to hardship. chronic stress and lead to other more or less chronic health problems as well as decreased productivity and motivation . Stress can also be encouraged by the provision of obsolete hardware or software, which wastes time or does not work properly and slows down the proper execution of tasks.
To prevent and limit the problems associated with working on a screen , it is necessary to limit the potential causes at the same time at the level of management but also at the level of ergonomics. By spending more than 7 hours a day at work, employees need adapted and personalized equipment according to their needs in order to be able to carry out their work safely and in a comfortable manner to limit the disturbances that may arise.
In this context, call on an ergonomist can help you analyze risky situations and benefit from practical recommendations to improve the working environment of your employees by means of various ergonomic solutions to be implemented.
First step for a ergonomic workspace : the location of the office.
The idea here is to determine the most optimal location where to place the work desks, depending on the size of the room, the storage furniture to be placed and the movement of people in the environment. Work surfaces must take into account the size and number of equipment to be placed (number of screens for example), the orientation must be defined by the direction of movement but also by the light sources to avoid reflections on the screens which would interfere with vision. Circulation should be as fluid as possible, with a sufficient free space between the various offices and easy access to the various work equipment (printers and photocopiers, archives, cabinets, etc.).
The workspace must also comply with the recommendations for promote the movement of people with reduced mobility in order to adapt to everyone (both employees and partners or customers).
To work in good conditions, physical work environments are also essential to take into account. Brightness, whether natural or artificial, is governed by article R-232-7-1 of the Labor Code. This specifies that “The lighting must be designed and produced in such a way as to avoid visual fatigue, as well as the resulting visual problems, and to make it possible to identify the risks perceptible by the sight.”
The premises should also benefit as much as possible from sufficient natural light , and the lighting level must be “ adapted to the nature and precision of the work to be performed. "
In addition to the brightness, the ambient noise is also important to take into account, especially in open spaces. Certain professions require concentration, which can be disrupted by phone calls, passages or conversations between colleagues, or even machines in certain sectors of activity.
To limit noise, various solutions can be implemented such as the installation of acoustic partitions or silent closing cabinets. Note that according to regulations, ambient noise must never exceed 87 dB .
With regard to the temperature of the workspace, the CSA Z412-17 standard recommends in summer a optimum temperature of 24.5 ° and 22 ° in winter, with a humidity level by 50%.
Once the working atmosphere has been optimized, make way for personal work equipment! The workstation layout should be designed to minimize the risk of discomfort. If the ideal posture is difficult to achieve and especially to maintain, several recommendations can be put in place in terms of ergonomics:
• The feet are resting flat on the ground , naturally or using a footrest if the chair or desk cannot be adjusted in height;
• The angle of the elbow is law or slightly obtuse,
• The forearms are close to the body,
• The hand is in the extension of the forearm,
• The back is straight or slightly behind, and supported by the record.
At the level of the chair, it must be ergonomic preferably, and include a adjustable backrest and seat . The armrests should also be adjustable in height. The seat should be neither too firm nor too soft to provide good lumbar support, and should be made if possible in a breathable fabric to ensure good comfort throughout the day.
Note that the chair must be perfectly suited to the physical condition of the employee, with adjustments if necessary, for example in the event of back or neck problems.
About the working screens , these must also be optimally adjusted to limit visual fatigue and tension in the neck and back. The top of the screen should therefore be placed at eye level , and the distance between the eye and the screen should be between 50 and 70 cm according to its size to ensure optimal comfort. If the employee works on two or more screens, the main screen should be placed in front of this one. With 3 screens, these must be placed in an arc.
Increasingly widespread with the health crisis and the increase in teleworking, the working on laptop must also be the subject of special attention because it also involves significant risks. Where possible, a independent keyboard and mouse should be used to avoid the risk of MSDs. The height of the screen is essential here: a booster can thus be used to avoid twists in the neck area.
For keyboard-mouse peripherals, we recommend a keyboard whose thickness does not exceed 3 cm . A wrist rest can be added to promote comfort.
The keyboard must be located in front of the employee but not at the edge of the work surface to allow the occasional support of the hands and forearms with a recommended distance of 10 to 15 cm between the edge of the work surface and the keyboard space bar.
The mouse must have an ergonomic shape, suitable for hand size . It can be placed in line with the shoulder, always keeping the forearm resting on the table.
To further improve ergonomics and effectively prevent the risks associated with working on screens , several ergonomic comfort solutions can be adopted depending on the points identified during the analysis in the field.
We can for example cite the ergonomic document holder , very useful for the professions which require the consultation of documents in order to avoid the tensions at the level of the neck and back.
Back support may also be recommended for back pain or lumbar pain, as well as a laptop riser during telecommuting days or on business trips.