ZERO leads the industry in designing and testing engineered intumescent systems for solving positive-pressure challenges. Our practical understanding of doors, combined with hands-on experience in testing, has led to the development of special-purpose intumescent formulations, which have established the quality and performance standards for North American openings.

   Developed by ZERO, SOFT PUFF intumescence is designed to deliver the performance best suited for protecting clearances and gaps in fire-door assemblies against penetration by flames and superheated gases. It has earned widespread acceptance for that purpose in the U.S.

   Our FS-3003 INTUMET is rubber-matrix material produced using soft-puff technology. When exposed to heat or fire, FS-3003 begins intumescing at relatively low temperatures to provide protection at the range where most organic materials begin to emit combustible and noxious gases. It expands gradually and equally in all directions to fill all gaps, with moderate force that will not crush or unlatch the door. FS-3003 forms a firm char that blocks penetration by superheated gases, smoke and flames for up to three hours. It is designed with a sufficient reservoir to continue intumescing if escape doors are closed again.

   The unique combination of attributes in soft-puff intumescence provides particular benefits for wood doors and metal temperature-rise doors, which require low heat rise on the unexposed face for the first 30 minutes. Where use of hard-puff intumescents would result in a prolonged interval where smoke and superheated gases can threaten life safety--or a successful fire rating--soft-puff materials literally fill that critical gap in protection. In addition, the new cotton-pad measurement of superheated gases on temperature-rise doors may require the use of soft-puff intumescence.

   ZERO FS-3003 material satisfies all major U.S. and international fire and smoke standards. It is mortised into door edges, stops or frames for both new and retrofit applications, thus avoiding the installation and liability problems associated with use of surface-mounted gasketing in a field environment.

   This material can also be integrated into door gaskets to protect from ambient as well as warm smoke. Neoprene or vinyl seals in the gaskets block smoke penetration at temperatures below the activation point of the intumescent material; and the intumescent seals then maintain the integrity of the sealing system at higher temperatures.

   FS-3003 INTUMET is available in any thickness, any width up to 12 inches, and can be ordered in custom colors. To ensure the long shelf life necessary for reliable, consistent performance, ZERO seals each intumescent strip with vinyl coating.