Sandwich panels, particularly those with cement facings like EPS cement sandwich panels, are not flammable primarily due to the materials used in their construction.
Here's why Sandwich panels resist fire:
1. Cement Facings
Inherent Fire Resistance: Cement is a non-combustible material, meaning it does not burn or contribute to the spread of fire. The cement facings on both sides of the panel act as a protective barrier, shielding the core from direct exposure to flames.
Thermal Insulation: Cement facings also have good thermal properties, helping to slow the transfer of heat to the panel's core, further enhancing fire resistance.
2. EPS Core Treatment
Fire-Retardant Additives: The EPS (Expanded Polystyrene) core is often treated with fire-retardant chemicals during manufacturing. These additives help reduce the material's flammability, causing it to melt or shrink away from heat rather than ignite easily.
Limited Oxygen Supply: In a sandwich panel, the EPS core is encapsulated by the cement facings, which restricts the amount of oxygen that can reach the core. This lack of oxygen hinders the combustion process, making it more difficult for the core to catch fire.
3. Panel Construction
Layered Structure: The sandwich structure, with the EPS core sandwiched between non-combustible cement layers, means that even if the core were to become hot, the outer layers would prevent the fire from spreading quickly.
Adhesive Properties: The adhesives used to bond the layers in sandwich panels are also typically chosen for their fire-resistant properties, contributing to the panel's overall fire performance.
4. Building Code Compliance
Fire Testing and Certification: Sandwich panels are often subject to rigorous fire testing to ensure they meet specific building codes and standards for fire resistance. These standards require the panels to withstand fire exposure for a certain period without igniting or spreading flames.
Summary
Sandwich panels are not flammable due to the combination of non-combustible cement facings, fire-retardant treatments in the EPS core, and the panel's overall design that limits oxygen access and heat transfer. This makes them a safe choice for construction, especially in buildings where fire resistance is a critical concern.