Which material is not commonly used in the construction of structural firefighting protective coats?

Structural firefighting protective coats are designed to provide firefighters with protection against extreme heat, flames, and other hazards encountered during firefighting operations. Common materials used in the construction of these protective coats include Nomex, PBI, and Kevlar, all of which are specifically engineered to withstand high temperatures and provide thermal protection.

Nomex is a flame-resistant synthetic fiber known for its heat resistance, making it ideal for protective gear. PBI is also a flame-resistant material, often used in high-performance firefighting gear due to its excellent thermal stability and strength. Kevlar is recognized for its high tensile strength and is often used for its protective qualities, especially in situations where cutting or abrasion resistance is necessary.

In contrast, fiberglass is not typically used in the construction of structural firefighting protective coats. While fiberglass does provide some level of heat resistance, it is more commonly associated with insulation materials or other construction applications rather than direct protective clothing for firefighters. Therefore, due to the specific fire-resistant properties required for protective coats, fiberglass would not be a suitable choice compared to the other mentioned materials.