Personal computer ergonomics; explained through examples
Published: May 30, 2021. Last updated: Jun 23, 2021.
Without the knowledge of how to sit, stand and otherwise use your body in a healthy, long term sustainable, ergonomic way, you will fall back to positions that intuitively feel comfortable in the short run, but can be harmful in the long run.
Below you will be guided through several aspects of ergonomics in the setting of using a personal computer, by using photo examples. You will get the most out of it by following the links with more information.
The keyboard is full size, not allowing the user to place it directly in front of him, and not allowing the person’s arms to stay within a comfortable range of motion compared to their shoulders. Avoid a full size keyboard when using a mouse.
The keyboard and trackpad of a laptop as a combination are too narrow, continuously keeping the person’s arms and hands in a closed and uncomfortable position. Avoid a keyboard and trackpad of a laptop for extended periods of time.
The keyboard of a laptop makes it harder to type by feel, increasing errors and so increasing the required motions of the already uncomfortable positions of arms and hands. Avoid a laptop keyboard for extended periods of time. It is designed portability, not ergonomics.
The keyboard is narrow enough to allow it to be placed directly in front of the user at a straight angle, and to allow the person’s arms to stay within a comfortable range of motion compared to their shoulders.
The single screen allows it to be placed directly in front of the user. The size of the screen allows it to be placed at a healthy distance from the eyes, and allows space on the desk to rest the arms and write on paper.
A dual screen setup does not allow the user to comfortably sit. This will negatively affect one or more of the person’s: hands, arms, legs, back, shoulders, neck and eyes. Choose one screen that is right in front of you, and look for reasons and methods how you can work without a second screen.
The top-most part of the image of the screen is at eye level, allowing the person’s neck to keep straight. The screen should not be higher or lower for extended periods of time.
The person’s neck is resting on his shoulders. The shoulders are resting on his spine. This reduces effort of the muscles, reduces pressure on the nerves, and allows optimal bloodflow.
His head is oriented straight forwards, which is signified by the direction of his eye sockets and by the front of his face until the chin, which is parallel to his upper body. This evenly distributes pressure on the neck, and positions the lower jaw correctly, and with that also the position of the tongue. All of this stimulates healthy nose breathing.
The person’s neck is not resting on his shoulders. There is tension in the neck.
His vertebrae are not stacked in the direction of gravity, and because they are not completely supported, there are pressure points outward on the intervertebral discs, spinal nerve and spinal cord.
The pelvils is oriented in such a way that the sitting bones are facing in a forwards direction, causing tension on the lower back and muscles.
Both person’s vertebrae are stacked in the direction of gravity, which prevents outward pressure on the intervertebral discs, spinal nerve and spinal cord. The pelvis is oriented in such a way that the spine can pass on the pressure in a straight line to the sitting bones, which are facing downwards.
