Articles
Worker seat (chair) of operator
Worker seat (chair) of operator should include the following basic elements: seat, backrest and arm-rests. As additional units can be a headrest and support for legs.
The construction of a seat should provide maintenance of a physiologically rational working pose by operation on the PC, allow to change a pose with the purpose of lowering static power of muscles of cervical - humeral area and spins for warning development of fatigue.
As a result of an incorrect working pose the diseases of a locomotorium, it can be:
- Osteochondrosis of a lumbosacral department of a backbone - as a result of a static inconvenient pose;
- The osteochondrosis of cervical and thoracal departments of a backbone - results from operation with incorrect bearing;
- Syndrome of the upper aperture of a thoracal cell;
Overеtense of muscles of a neck, brachium and breasts bringing to aggravation blood supplies and realization of nervous impulses;'
- Infringement of a brachium (the sharp omalgias) - of a tendon are squeezed between the head of a humeral bone and process of a scapula;
- Scoliosis (side rachiocampsis) - a too hard or too soft seat, incoordination of height of a seat with the anthropometric user profiles;
- The hemorrhoids - results from an inactive image of life, incorrect landing, construction of a seat.
The seat should be rotary and adjusted for height and slope angles of a seat and backrest, and also distance of a backrest from front edge of a seat, thus the regulation of each parameter should be independent, easily exercised and to have reliable fixing.
The surface of a seat, backrest and other units of a chair should be halfsoft, with not slipping, not electrified, moisture pushing away and air-permeable coating providing mild clearing from contaminating.
The worker chairs (seat) for pupil and students should correspond to body height of the pupils or students in footwear (tab. ).
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Main sizes of a chair for the pupil and students |
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Body height of the pupils and students in footwear, sm |
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Parameters of chair |
116-130 |
131-145 |
146-160 |
161-175 |
выше 175 |
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Height of a seat above a flat, mm |
300 |
340 |
380 |
420 |
460 |
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Width of a seat, not less, mm |
270 |
290 |
320 |
340 |
360 |
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Depth of a seat, mm |
290 |
330 |
360 |
380 |
400 |
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Height of lower edge of a backrest above a seat, mm |
130 |
150 |
160 |
170 |
190 |
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Height of upper edge of a backrest above a seat, mm |
280 |
310 |
330 |
360 |
400 |
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Height of a line of a sag of a backrest, not less, mm |
170 |
190 |
200 |
210 |
220 |
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Bend radius of front edge of a seat, mm |
20-50 |
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Slope angle of a seat, hailstones. |
0-4 |
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Slope angle of a backrest, hailstones. |
95-108 |
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Radius of a backrest in the schedule, not less, mm |
300 |
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