Intumescent Fire Dampers & Fire Rated Air Transfer Grilles
For those who may not be familiar, intumescent materials are widely used in passive fire protection. The dictionary definition of intumescent is as follows: An intumescent substance is one that swells when exposed to heat, resulting in an increase in volume and a decrease in density. Intumescence refers to the swelling process. Intumescent materials are typically used in passive fire protection, where the swelling is a chemical reaction that forms a char, which continues to expand and seals off openings.