Back problems are often caused by seats that do not meet the requirements of the modern Office. Most of us are accustomed to bending and we do not know when to begin improving the way we sit. We sit on seats that are not designed to meet the modern requirements of our physique.
As far as the size of the office surface is concerned, it is determined by the space available and the type of work for which it is intended. However, it is important that the floor height does not exceed 0.75 million meters, since the average height of the man, is 1.70 meters.
The seat despite the long history of 2050 - 1600 BC,has so far been poorly designed and this is duethe anthropometric and anatomical features of the person using it.
An skjorte til mænd in orded to be successful must fit on Anatomical Dimensions of the human being who uses it in order to offes comfort, ease of operation, efficiency and safety. In other words, the seat is like a "shoe". The same
number does not fit all "legs".The seat intended for young people does not serve as comfortable for the elderly who need different specifications and constructions.
The very logical approach should therefore govern the choice of the seat type according to its age, intended use (work - study) and working hours - design, determining its construction.
A) Center of Gravity
The center of body weight of a person sitting on a ground-parallel seat and back in a right angle to it is a vertical conceivable line that passes 2.5 cm in front of the center of the chest and meets the ground.
When the seat does not provide adequate stabilization, the person is instinctively attempting to stabilize his weight changing attitudes on the seat. This process causes the consumption of bodily energy and creates the impression of the unobstructed seat. The weight distribution of the human body on a seat is 75% of the weight on the seat, 8% on the back and 17% on the floor.
B) The Seat Height
One of the basic requirements in the design of an ergonomisk siddemøbel is the height of the seat from the floor. Particular importance should be given to the pressure that the foam (polyurethane foam) receives from the body weight and how much the original seat height is reduced.
When the ergonomisk siddemøbel surface is high enough for the man, the muscular surfaces under his thighs are pressed against the seat by their weight, thus limiting the circulation of blood to those points. Equally bad is the seat height does not allow comfortable and complete contact of the feet on the floor so the body's stability decreases. Also, when the seat is low enough, the legs are forced to extend far in front of the seat, thereby shifting the center of gravity and forcing the body trunk to close forward and away from the back support surface. The height adjustment range for a seat is between 37.5 and 52.5 cm for adults, with an average height of 43 cm, serving the largest proportion of adults.
When the seat height is up to 38 cm, it serves a relatively large number of adults, except that large people will need space for their extended legs and cause a problem getting them up.
C) Seat Depth
A basic prerequisite for the design of an ergonomisk siddemøbel is its depth, and the distance from the front of the seat to the back surface.
When the seat depth is large enough, the front of the seat presses the legs just behind the knees, thus limiting the blood circulation to and from the ends of the legs. People who, due to their work, are forced to sit many hours a day are so dangerous to cause "Thrombophlebitis".
The man who uses a deep-seated seat and tries to move his body further out to avoid this pressure, thereby increasing the distance of his body from the backrest, thus causing back and lumbar pain country "back pain".
On the contrary, when the seat has a small depth, it restricts the total support of the thigh muscular surfaces on the seat causing the body to feel tilted forward.
D) The seat angle (Seat Angle)
The slopes of an ergonomisk siddemøbel are always measured in relation to the vertical axis of the back to the floor with a slope of forward and backwards recall.
E) Seat Padding Materials (Seat Padding)
Foam materials aim at smoothly distributing body weight over the seat surface. The notion that the deeper and softer ergonomisk siddemøbel is, the more comfortable it is, it is not right. The soft-filled deep seat causes the sciatic bone to sink deep into it, resulting in the entire body weight burden being transferred to the surrounding muscles and causing local pains. These with regard to the seat of the seat.
F) Back - rest
The design of the back should necessarily support the lumbar region and, depending on its height, also support the chest and touch the spine with the corresponding curvature.
1. Lumbar Support
The back of the seat does not support the lumbar region properly
and the spine can cause severe pains.
2. Thoracic Support
The minimum backrest height for lumbar support
and chest area is 50 - 55 cm.
3. Sacrum Support
The seat of the seat must have the corresponding curvatures and
the formed foam materials follow its periphery
basin in a way to ensure comfort and avoid pressure
in the area of the coccyx.
H) Bracket Arm Supports
Supporting the seat armrest relieves the muscles from the weight of the shoulders and the hands themselves. The height of the arms should be at least at the same height or higher than the desk or counter so as not to rub the forearm at the niche of the desk or work surface. For this purpose, we recommend that the arms are height-adjustable to accommodate the height of the desk or work surface and the length of the forearm, thus reducing the incidence of carpal tunnel syndrome and hand tendonitis, often seen in computer users and those doing sedentary jobs such as silversmiths, radio technicians, dental technicians, or other activities.
An essential complement to a good ergonomisk siddemøbel is the Footrest and even reclining because:
Helps blood circulation of the lower limbs.
It relieves the muscular system from long hours of inertia and
Offers a balanced distribution of body weight