Office Chair Fire

An office chair fire falls under solid-material fires (Class A) and requires a water-type fire extinguisher for suppression. According to fire classification standards, Class A fires are caused by the combustion of carbon-containing solid combustibles, and the main materials of office desks and chairs (wood, metal, or plastic) all meet this characteristic. For example, the case of a factory in Jinhua, Zhejiang, on March 5, 2025, where lit incense sticks ignited office desks and chairs, clearly demonstrates a typical scenario of such fires. The following provides an explanation from three aspects: fire causes, classification basis, and suppression methods.

Fire Causes and Material Associations

The combustion of an office chair usually stems from its combustible materials directly contacting a fire source. Wood, as the main material of traditional office furniture, produces open flames and a large amount of smoke when burning. Plastic materials (such as chair backs and armrests) melt and release toxic gases at high temperatures. Although metal frames are not easily flammable, if they are coated with a flammable paint layer or come into contact with combustibles, they can still serve as a medium for the spread of fire. In addition, if an office chair is equipped with a low-quality gas spring, the high-pressure gas inside may explode due to high temperatures or mechanical damage. However, the explosion itself is a physical mechanical failure, and the combustion process is still dominated by solid materials, so it is still classified as a Class A fire.

Fire Classification Basis

The core characteristic of a Class A fire is that the combustible material is a carbon-containing solid. Among the materials of office chairs, both wood and plastic contain carbon elements. When burning, they undergo oxidation reactions, generating products such as carbon dioxide and water vapor. Although metal materials do not contain carbon, in actual fires, metal frames are often combined with wooden or plastic components, and the surface coatings of metals (such as paint) are mostly organic substances, which also conform to the characteristics of Class A fires when burning. Therefore, regardless of the main material of an office chair, its fire type is uniformly classified as Class A.

Suppression Methods and Precautions

For Class A fires, a water-type fire extinguisher is the preferred suppression tool. Water reduces the temperature of the burning material below its ignition point through cooling and dilutes the oxygen concentration with water vapor to suppress the spread of the fire. If the fire is small, a fire blanket can also be used to cover and extinguish it, or sand can be used to bury and isolate the oxygen. It is important to note: If the office chair contains a low-quality gas spring, stay away from the explosion risk area before suppression to avoid secondary injuries caused by the explosion of the gas spring. If the fire has spread to electrical wiring (such as in an electric office chair), cut off the power supply before suppression to prevent electric shock accidents.

In daily prevention, avoid using open flames in office areas, regularly check the safety of components such as the gas springs of office chairs, and choose furniture made of fire-retardant materials to reduce the risk of fire.