As an option, an STI intumescent band (UL-Approved Material) may be installed within the Daisy housing. In the event that outdoor air passing through the Daisy exceeds 320 degrees F, the intumescent material will expand within seconds, totally blocking entry of heat, smoke and water spray, thereby protecting the occupants and interior of the dwelling from fire, smoke, heat and water spray entry through the fresh air port for hours .
Radon Mitigation With "Smarts"