Three-Dimensional Dimensions of Office Chairs

The three-dimensional dimensions of office chairs should be designed according to ergonomic principles and usage scenarios, with core parameters as follows:

1. Seat Height The standard range is 400-500 millimeters, and it is recommended to choose an adjustable model with a typical adjustment range of 6-12 centimeters (some high-end models support 24-30 centimeters). This design can accommodate users of different heights, ensuring that the thighs are parallel to the ground and the feet are flat on the floor. For example, users under 170cm in height can adjust the seat height to 400-430 millimeters, while users over 180cm in height may need 450-500 millimeters.

2. Seat Depth The seat depth of ordinary office chairs is 38-44 centimeters, ensuring that the buttocks are snug against the backrest and leaving about a 5-centimeter gap (a fist's distance) between the calves and the edge of the seat to avoid compressing the leg blood vessels. Due to space constraints, the seat depth of partitioned office chairs may be shortened to 35-40 centimeters. For users with larger body types, it is recommended to choose a seat depth of 42-44 centimeters to enhance comfort.

3. Seat Width The common size is 450×450 millimeters, with the width of the widened seat being ≥50 centimeters. Some models (such as executive chairs) are designed to be 57 centimeters wide to accommodate larger users. The widened design can disperse pressure on the buttocks, reduce fatigue from prolonged sitting, and is particularly suitable for employees with a BMI index exceeding the standard (≥28).

4. Armrest Height The standard range is 21-22 centimeters, which should match the height of the desk (usually 75-78 centimeters) to keep the elbows naturally bent at 90 degrees when the hands are flat on the desk. For special scenarios (such as resting), the armrest height can be adjusted to 20-23 centimeters to support arm relaxation. Conference room chairs need to appropriately widen the armrest spacing (usually ≥50 centimeters) to facilitate sitting with coats on.

5. Backrest Height The backrest height of work chairs is 46-61 centimeters, while that of executive chairs or large office chairs can reach 48-63 centimeters and are equipped with headrests (the support point is about 55-65 centimeters from the seat). The high backrest design can support the area from the shoulder blades to the lumbar spine, reducing spinal pressure, while the headrest supports the neck to prevent cervical spine strain.

6. Special Design Parameters

• Lumbar Support: It is recommended to adopt an arc-shaped design with a height of 15-20 centimeters and a thickness of 5-8 centimeters to fit the natural curvature of the lumbar spine.
• Chair Foot Wheelbase: A five-claw chair foot wheelbase with a diameter of ≥65 centimeters can prevent tipping over, especially suitable for users with a larger weight (≥90kg) or frequent movement.
• Load-Bearing Capacity: The standard load-bearing capacity of office chairs is 100-120kg, and reinforced models can be customized to over 150kg, achieved through thickened steel frames or high-density sponge.

Design Basis: The above dimensions are all based on ergonomic principles and need to meet the needs of different body types through adjustable functions (such as customizing widened seats and reinforced load-bearing structures for employees with a BMI exceeding the standard), while also taking into account space utilization and usage scenario adaptability.