Many of us have experienced sudden pain in arms, neck, shoulder, back or even darkness in vision after continuous work behind desks and probably never care about it due to the various engagements which are a part of today’s life style. However, it is possible to improve physical condition and remove pains resulting from previous unfavorable conditions just by changing physical state such as sitting position or choosing proper work chair, desk or etc. To achieve this desired situation, following points must be carefully taken into account:
1: choose best and most suitable work chair.
2: choose work chair that satisfies physical and medical standards for our job.
3: choose proper desk and keep the standard distance between chair and desk.
4: observe the sitting principles and body position during sitting and standing.
5: observer distance and correct direction of light source.
6: Give rest to eyes during work and use of monitor and its standard distance from work chair must have special characteristics in respect to the career and profession. For example, a person who works with computer and sometimes lean back must use a work chair that its back is flexible.
If work chair does not have head rest, usually the best sitting angle is about 110 degrees. This angle, in principle of sitting, press less pressure to the back and is useful for working with computer and sitting in classrooms. If the chair has head set, this angle could be even more.
For work chair, the height of chair should not be so high that person’s foot does not reach floor and also it should not be so short that back of thigh has some distance from chair surface and even make the legs go toward belly.
The seat bottom should be soft but not like armchair that person goes deep into chair and cannot move, because in this position, blood will not flow correctly.
It is recommended that the chair have arms, so person puts his hands on them during rest time. It is also recommended that during work time , hands are not positioned on chair arms, because this position is not standard and may cause negative tension. The back seat should have a curve to preserve the lumbar while leaning. The seat bottom and back should be from proper material with some pores and If they are made from plastic, this material must have good quality. Back seat should be adjustable from 80 to 100 degrees, so to use it as a study or computer chair.
Note: using footrest depends on the chair and persons ‘height. For example, if the chair is tall and does not have height adjustment, it is recommended to use footrest, otherwise there is no need to use it. However, if the chair is short and does not have height adjustment, footrest can be used.