Bulge Inside Office Chair

A bulge inside an office chair may be caused by deformation of old springs, ergonomic design, or safety hazards, and needs to be addressed according to the specific situation.

Analysis of Bulge Causes

1. Bulge from Old Seat Springs
   The internal springs of an office chair that has been used for a long time may deform due to metal fatigue, forming a single-point bulge. This type of bulge will directly press against the perineal area. Although there is no stinging sensation, it will slowly increase bladder sensitivity, leading to frequent urges to urinate after sitting for a long time. Male users often overlook the internal structure of the seat and fail to replace or pad it flat for a long time, causing the problem to recur.

2. Bulge from Ergonomic Design
   Some office chairs adopt a "higher at the front, lower at the back, and bulging in the middle" design to adapt to the elastic properties of mesh materials. When sitting down, the mesh sags, and the bulging part can form a supporting surface that fits the body's curves, enhancing comfort. However, users weighing over 90kg may experience pressure on the underside of their thighs due to excessive sagging of the mesh, leading to leg numbness.

3. Safety Hazards
   In rare cases, bulges inside the seat may form sharp edges due to manufacturing defects or material aging, posing a risk of cuts. There have been reports of users suffering severe injuries due to exposed metal parts inside the seat.

Countermeasures

1. Regular Inspection and Maintenance
   Inspect the condition of the seat springs every six months. If deformation is found, promptly add a flat cushion to fill in the uneven surface. If the fabric sags severely, replace it with a high-density sponge or memory foam cushion to distribute pressure and avoid single-point pressure.

2. Adjust Sitting Posture
   When sitting down, slightly adjust your posture to transfer the pressure point to the gluteal maximus area, avoiding the perineal area. You can try placing a folded towel or soft cushion on the bulge to temporarily relieve pressure.

3. Replace the Seat in a Timely Manner
   If a seat that has been used for more than 5 years shows significant deformation, it is recommended to replace it entirely. When purchasing, prioritize products that have passed BIFMA certification to ensure that the springs and frame structure meet safety standards.

4. Weight-Appropriate Selection
   Users with a larger body weight (>90kg) should avoid choosing seats with mesh materials or opt for versions with thicker cushions to prevent excessive sagging of the mesh and pressure on the legs.