Although the main function of a duct ventilation system in a building is to allow the movement of air around that building via those ducts, where there is fire however these ducts could provide a means for the fast spread of fire and smoke. Some buildings may already have fire resistant duct systems installed, but for those which don’t dampers may need to be retrospectively installed at each fire boundary. Such a system can be activated / operated by the use of mechanical, electrical and intumescent components. Intumescent materials however have some very important advantages.

How Intumescent Material Reacts to Heat and the Absence of Moving Parts. When fire takes hold in building the extreme conditions, high temperatures, different pressures and other destructive forces could cause distortion and jamming of mechanical parts. Where Fire Rated steel mechanical dampers are used to close blades, or in Fire and Smoke Rated dampers where an electrical system is linked to the smoke detectors and fire alarms are used to close blades in the ventilation system there is a reliance on moving parts and components to ultimately stop the spread of smoke and flames. This carries a risk of failure of one or more of those parts. The very nature of intumescent material however is to react to heat by expanding. The material itself will always react the same way. Therefore the use of Intumescent materials in fire and smoke dampers for ventilation systems adds a failsafe element when incorporated in mechanicals and electrical systems, or when used on their own.

Minimum Maintenance. Access to dampers in ventilation systems in some modern buildings can be difficult and therefore inspection and proper maintenance routines could be challenged. Also the mechanical and / or electrical elements of those systems may naturally require maintenance. Intumescent dampers however require minimum maintenance e.g. perhaps some cleaning in extremely dirty conditions.

More Scope In Installation Tolerances. Even if the Intumescent dampers are distorted (within reason) during installation they should still react to a degree where they are reliable.

Light and Compact. Intumescent material sections are generally light, compact and slim and this can make them relatively easy to install correctly.

Cost Effective. The kinds of Fire and Smoke Rated dampers which use intumescent materials tend to be cost effective because they only need low voltage and low levels of power to operate.

Consider Using Duct Fire Sleeves

Reinstating the fire rating of a wall or floor that has ventilation ducting passing through it can be easily achieved by adding intumescent duct sleeves. They don’t require mastic or screws, they’re available in rectangular and circular form, and they also work well as an acoustic barrier.