Explosion of Faulty Office Chairs

The explosion of faulty office chairs typically refers to the sudden explosion of pneumatic lift swivel chairs caused by component defects, often due to inferior pneumatic rods, and the risk can be reduced through proper selection and use.

Causes of Explosions and Typical Cases

The core cause of explosions in pneumatic lift chairs is defects in the quality of the pneumatic rods, specifically including:

1. Thin Walls of the Pneumatic Rods: To reduce costs, inferior pneumatic rods have insufficient wall thickness, making them unable to withstand the repeated impact of high-pressure gas (usually inert nitrogen gas) inside. After prolonged use, they are prone to rupture.
2. Insufficient Purity or Substitution of Gas: Legitimate pneumatic rods should be filled with high-purity nitrogen gas, but inferior products may be mixed with air or directly use compressed air. Nitrogen is chemically stable, while the oxygen in air may support combustion at high temperatures, increasing the risk of explosion.
3. Temperature Increase Due to Frequent Lifting: Pneumatic rods achieve lifting through gas compression. Frequent operation raises the internal gas temperature, and if there are defects in the rod walls, the high temperature accelerates material fatigue, leading to rupture.

Historical cases confirm these risks:

• In 2007, in Zhoushan, Zhejiang, a pneumatic chair explosion injured a user;
• In 2009, in Jiaozhou, Shandong, a 14-year-old boy was fatally injured when the rod of a pneumatic chair pierced his body during adjustment;
• In 2013, in Xiamen, Ms. Liu was sitting on an online-purchased swivel chair while blow-drying her hair when the chair suddenly exploded. A steel rod with a diameter of 3 centimeters penetrated her lower body, and more than ten metal fragments were removed from her abdomen.

Quality Issues and Regulatory Status

According to a spot check by the State Administration for Market Regulation, the failure rate of office chairs reached 23.3% in 2020, with 17 batches being swivel chairs. The main issues were concentrated in:

• Inadequate High/Low Temperature Resistance of Pneumatic Rods: Temperature changes may cause the material of the pneumatic rods to contract or expand, leading to rupture in inferior products;
• Lack of Explosion-Proof Steel Plates: Explosion-proof steel plates, located between the seat cushion and the pneumatic rod, should have a thickness of at least 2 millimeters to block fragments in the event of an explosion. The absence or insufficient thickness of these plates directly threatens user safety.

Preventive Measures and Purchase Recommendations

To reduce risks, the following practices should be followed:

1. Choose Products from Legitimate Manufacturers: Prioritize purchasing products priced above 200 yuan to avoid low-quality, inferior products;
2. Check the Smoothness of Pneumatic Rod Lifting: Legitimate pneumatic rods should lift smoothly without stuttering. If there are unusual noises or uneven resistance during lifting, internal defects may be present;
3. Confirm the Installation of Explosion-Proof Steel Plates: Before purchasing, request product cross-section diagrams or disassembly videos from the seller to confirm that there is an explosion-proof steel plate with a thickness of at least 2 millimeters between the seat cushion and the pneumatic rod.

By following proper selection and correct usage, the risk of explosion in pneumatic lift chairs can be effectively avoided.