Height of Office Chair and Boss Chair

The standard height range for office chairs and boss chairs is typically 40-50 centimeters, with specific adjustments required based on ergonomic principles and actual usage needs.

I. Standard Height Range and Core Objectives

According to national standards, the height design of office chairs and boss chairs aims to maintain a perpendicular angle between the thighs and lower legs when seated, with approximately 5 centimeters of space reserved behind the knees. This range prevents excessive pressure concentration in the legs due to a chair that is too low and avoids foot suspension or forward leaning of the waist caused by a chair that is too high. If the chair is too high and the feet cannot touch the ground, it is recommended to use a footrest to maintain proper sitting posture.

II. Ergonomic Adjustment Principles

The scientific adjustment of chair height should be based on the sum of the user's calf窝 height (fibular head height) and heel thickness, minus an activity allowance of 10-20 millimeters. For example, if the user's calf窝 height is 450 millimeters and the heel thickness is 20 millimeters, the chair height should be set to 450 + 20 - 15 (taking the middle value) = 455 millimeters. This formula ensures that when the legs hang naturally, the soles of the feet can rest flat on the ground while avoiding pressure on the back of the knees (popliteal fossa) from the edge of the seat.

III. Seat Surface Material and Height Restrictions

Different seat surface materials have varying height requirements:

• Soft Seat Surface: The maximum height should not exceed 460 millimeters. Excessive height in a soft seat can lead to compression deformation, reducing the actual sitting height and potentially causing uneven pressure distribution in the legs.
• Hard Seat Surface: The recommended height range is 400-440 millimeters. Hard seats have minimal deformation and greater height stability, making them more suitable for scenarios requiring prolonged fixed sitting postures.

IV. Verification Standards After Adjustment

After adjustment, verify the height suitability through the following methods:

1. Feet Touching the Ground Test: When seated, the feet should naturally rest flat on the ground without the need to deliberately tiptoe or bend the knees.
2. Palm Insertion Test: There should be enough space to easily insert a palm (approximately 3-5 centimeters gap) under the thighs, indicating that the chair height matches the leg length.
3. Back of Knee Pressure Test: The front edge of the seat should just touch the back of the knees without causing pressure. If there is significant squeezing, it indicates that the chair height is too high or the seat has an excessive forward tilt angle.

By scientifically adjusting the chair height, you can effectively reduce fatigue from prolonged sitting, prevent occupational diseases in the lumbar and cervical spine, and enhance work efficiency and comfort.