Which materials are commonly classified as non-combustible?

Non-combustible materials are those that do not ignite or burn when exposed to fire or high temperatures. In the context of construction and fire safety, materials such as concrete, steel, and brick are commonly classified as non-combustible due to their inherent properties.

Concrete is a mixture of aggregates, cement, and water that, when cured, forms a hard, durable mass that is resistant to fire. It does not support combustion. Similarly, steel is a metal alloy that can withstand high temperatures without failing structurally for a considerable period, although it can lose strength at extremely high temperatures. Brick, made from clay and fired at high temperatures, is also non-combustible and offers good fire resistance.

These materials are often utilized in building structures due to their strength, durability, and ability to create fire-resistance ratings required by building codes, thereby offering enhanced safety in case of a fire. In contrast, the other materials listed in the other options—such as wood, plastic, fabric, glass, plaster, asphalt, paper, foam, and vinyl—are more likely to ignite and combust, making them unsuitable for classification as non-combustible.