Pneumatic Office Chair Accident

A pneumatic office chair accident mainly refers to the sudden explosion phenomenon of pneumatic lifting swivel chairs caused by component defects, which mostly occurs in low-quality pneumatic rod products. Prevention should start from three aspects: selection, inspection, and structure.

Causes of Explosion

1. Thin wall of the pneumatic rod: In some chairs where corners are cut, the wall thickness of the pneumatic rod does not meet the standards. When a person sits on it, the upper air chamber of the piston is compressed, and the air pressure can increase to 18 - 25 atmospheres, increasing the pressure on the cylinder wall and making the tube wall prone to rupture.
2. Insufficient purity of inert gas or replacement with compressed air: The oxygen in the air continuously reacts with the metal inner wall through oxidation, causing continuous rusting and heat accumulation, which leads to a sharp increase in internal pressure. The outer tube wall becomes thinner and more brittle, eventually triggering an explosion.
3. Frequent lifting and lowering leading to a sudden temperature rise: Frequent operations cause the internal temperature of the pneumatic rod to rise rapidly, accelerating gas expansion and metal fatigue, and increasing the risk of explosion.

Consequences of Explosion

Pneumatic office chair explosions can have serious consequences. High-speed fragments can pierce through the seat cushion and shoot into the human body. For example, in 2009, a 14-year-old boy in Jiaozhou, Shandong, was sitting on a chair when it exploded, and a steel rod pierced his abdomen, ultimately causing him to lose his life due to excessive blood loss. In 2013, when Ms. Liu was sitting on an online-purchased lifting swivel chair to blow-dry her hair, the pneumatic rod exploded, and a steel column with a diameter of 3 centimeters pierced through her body and into her abdominal cavity, with more than ten metal fragments removed from her abdominal cavity and intestines. In 2017, an office chair explosion in Anhui damaged a computer case.

Preventive Measures

1. Select products from regular manufacturers: It is advisable to choose products priced above 200 yuan and avoid buying low-priced and low-quality products. Regular manufacturers usually pay more attention to quality control and safety standards.
2. Check the smoothness of the pneumatic rod's lifting and lowering: When purchasing, test whether the lifting and lowering of the pneumatic rod are smooth without any stuttering or abnormal noises, which may indicate problems with the internal structure.
3. Ensure the installation of an explosion-proof steel plate between the seat cushion and the pneumatic rod: The thickness of the explosion-proof steel plate should be ≥ 2 millimeters, which can effectively block the fragments generated during an explosion and reduce the risk of injury.