What is the size of the general office chair？
According to the normal chair size design in daily life:
Seat height: between 400-450mm;
Sitting width: generally between 400-500mm;
Backrest height: between 480-630mm;
Angle between backrest and seat surface: 95°-105°.
1、Seat height of standard chair size
1.Seat height refers to the vertical distance from the seat surface to the ground; if the seat surface has a receding or concave arc shape, the seat height refers to the vertical distance from the center point of the front edge of the seat to the ground. If the seat height is too high, the legs will be suspended in the air and will compress the thigh blood vessels; if the seat height is too low, it will cause physical fatigue. Practice has proved that the appropriate seat height is the height from the calf socket to the sole of the foot plus the heel thickness of 25-35mm, and then minus 10-20mm of activity margin.
That is: seat height H = calf socket height + heel thickness - proper clearance.
2.The national standard GB 3326-1997 stipulates that the seat height H is 400-440mm, and the size difference is 10mm. The maximum height of the soft seat is 460mm (excluding the sinking of the seat). The height of the sofa seat can be lower, so that the legs are stretched forward and the backrest is tilted back, which is conducive to the natural state of the spine. The seat height of the sofa is generally 360-420mm.
2、Seat inclination angle and back inclination angle of chair size standard
1.The angle between the seat surface and the horizontal plane is called the seat inclination angle α; the angle between the backrest and the horizontal plane is called the back slope angle β.
2.The national standard GB 3326-1997 stipulates that the seat inclination angle α is 1-4 degrees (back chair and armchair), or 3-6 degrees (folding chair), and the angle difference is 1 degree; the back inclination angle β is 95-100 degrees ( back chairs and armchairs), or 100-110 degrees (folding chairs), with an angle step of 1 degree. For a sofa, α is 3-6 degrees, and β is 98-112 degrees; it is even larger for a recliner.
3、Seat depth of standard chair size
1.Seat depth refers to the distance from the front edge to the rear edge of the seat surface. If it is too deep or too shallow, it will cause fatigue and discomfort to the calves and lower back. Practice has proved that the seat depth should be slightly smaller than the horizontal length of the thigh when sitting. which is:
2.Seat depth T = the horizontal length of the thigh in the sitting position exceeds 60mm (gap)
3.The national standard GB 3326-1997 stipulates that the seat depth T is 340-420mm (back chair), or 400-440mm (armchair), or 340-420mm (folding chair), and the size difference is 10mm. For sofas and other leisure seats, the seat depth can be slightly larger, 480-560mm, due to the large backrest inclination.
4、Seat width of standard chair size
1.The seat width should be able to fully support the arm and leave room for it. For armchairs, the inner width of the armrest is the seat width, which is generally determined by the average person's shoulder width plus an appropriate margin.
2.That is: the inner width of the front edge of the armrest B = the width of the human shoulder + the thickness of the winter clothes + the activity margin
3.The national standard GB 3326-1997 stipulates that the front width B of the armchair or folding chair seat is greater than or equal to 380mm, and the size difference is 10mm; the inner width B of the front edge of the armrest is greater than or equal to 460mm, and the size difference is 10mm.
