Office Chair Explosion Due to Height Adjustment

The explosion of office chairs during height adjustment mainly refers to the sudden explosion phenomenon caused by component defects in pneumatic height-adjustable swivel chairs, which mostly occurs in low-quality pneumatic rod products. The causes, cases, and preventive measures are as follows:

Causes

• Principle and Hidden Dangers of Pneumatic Rods: Pneumatic height-adjustable rods are essentially miniature high-pressure pressure vessels that rely on air pressure to push the piston to achieve seat height adjustment. In qualified pneumatic rods from reputable manufacturers, high-purity inert nitrogen is filled inside, which is stable in nature and safe to control. A single qualified pneumatic rod can withstand a pressure of 2000 pounds. However, unscrupulous manufacturers, in order to save costs, replace nitrogen with cheap ordinary compressed air. The oxygen in the air will react with the metal inner wall through oxidation, continuously rusting and accumulating heat, turning the pneumatic rod into a sealed, continuously pressurized pressure cooker. The internal pressure soars, the outer tube wall becomes thinner and more brittle, and ultimately, an explosion may occur. In addition, a pneumatic rod with an overly thin tube wall, insufficient purity of inert gas, and frequent height adjustments leading to a sudden temperature rise can also trigger an explosion.

Explosion Cases

• In 2007, a seat explosion incident occurred in Zhoushan, Zhejiang.
• In 2009, a 14-year-old boy in Jiaozhou, Shandong, died after a top rod of a pneumatic chair pierced into his body while adjusting the chair.
• In 2013, Ms. Liu, after taking a bath, sat on an online-purchased height-adjustable swivel chair to blow-dry her hair. The pneumatic rod shot through her body from bottom to top like a cannonball, piercing into her abdomen. Dozens of metal fragments were extracted from her abdomen and intestines.
• In 2017, an office chair explosion in Anhui damaged a computer case.
• In Xiamen, a woman surnamed Lin was sitting on a height-adjustable chair to blow-dry her hair when the chair suddenly exploded. A 20-centimeter pneumatic rod flew out, and a large number of chair fragments shot into her body, with some metal screws also shooting into her abdominal cavity.

Preventive Measures

• Purchase Products from Reputable Manufacturers: It is recommended to choose products priced above 200 yuan. These products usually have stricter quality control, and the quality of key components such as pneumatic rods is more guaranteed.
• Check the Smoothness of Pneumatic Rod Height Adjustment: Before purchasing or using, check whether the height adjustment of the pneumatic rod is smooth and whether there are any stutters or abnormal noises. If there are abnormalities, it may indicate that the pneumatic rod has quality issues and should be avoided.
• Ensure the Installation of Explosion-Proof Steel Plates: A explosion-proof steel plate with a thickness of no less than 2 millimeters should be installed between the seat cushion and the pneumatic rod. This can to some extent block the fragments generated during a pneumatic rod explosion and reduce the harm to the human body.