Which material is commonly used to protect steel and wood structural members from fire?

Gypsum is widely recognized for its fire-resistant properties and is commonly used to protect structural members like steel and wood from fire. When exposed to high heat, gypsum releases water vapor, which helps to slow down the spread of flames and mitigates heat transfer. This makes it an effective fireproofing material, essential for maintaining the integrity of structural components during a fire.

In buildings, gypsum is often utilized in the form of drywall, fire-rated wall assemblies, and ceiling tiles. Its ability to withstand high temperatures and prevent structural failure under fire conditions is critical for enhancing the overall safety of a building. Additionally, gypsum board can be easily installed and finished, making it a practical choice for fire protection.

Other materials listed may possess different properties or advantages but do not provide the same level of fire resistance as gypsum. Lightweight concrete slurry, for instance, may be used for insulation or weight reduction, but it doesn't exhibit the same inherent fire-resistance capabilities. Fibreglass primarily offers insulation properties and does not effectively prevent the spread of fire. Expanded urethane, while useful in insulation, can be highly flammable and does not protect surfaces from fire damage.