Ductwork

Ductwork

The smoke and hot gases generated during a fire reach very high temperatures. Sheet metal ductwork manufactured to standard DW144 or SMACNA specifications deforms and changes shape under high heat, becoming unable to fulfil its smoke extraction function. Yet the vast majority of fatalities in fires result not from direct flames but from smoke inhalation.

Unprotected ventilation ductwork causes fire, smoke and toxic gases to spread rapidly through a building. In particular, smoke extract ductwork must be fire-resistant for the duration of the fire resistance of the wall or floor compartment through which it passes. It must also be proven by testing that it maintains its cross-sectional area under fire conditions and can continue smoke extraction under a certain pressure.

Standard ventilation ductwork does not provide fire resistance unless it has passed the relevant fire tests.

Fire-resistant duct systems tested to international standards and certified in accredited laboratories maintain the integrity of building fire compartments. These systems prevent fire and heat from spreading between different compartments whilst enabling safe smoke extraction to continue.

Firesol fire-resistant duct systems provide up to 4 hours of fire resistance for ventilation ductwork, ensuring building safety and smoke control performance.

Fire safety requirements vary according to system type:

• Mechanical Ventilation Systems – Remove stale air, supply fresh or conditioned air.
• Smoke Extract Systems – Exhaust smoke and toxic gases during a fire.
• Combined Ventilation / Smoke Extract Systems – Normally ventilate, extract smoke during a fire.
• Pressurisation Systems – Create positive pressure to prevent smoke entering critical areas (no fire dampers used).
• Car Park and Industrial Kitchen Extract Systems – Operate independently due to heavy contaminated air, no fire dampers used.

Fire-resistant duct protection is a critical safety requirement in the majority of these systems.

Fire-resistant ventilation ductwork is tested and classified in accordance with the following European standards:

EN 1366-1: Fire resistance test method for ventilation ductwork. The duct's integrity (E), insulation (I) and smoke extraction performance are tested.

BS 476-24: Performance test standard for fire-resistant ventilation systems.

ISO 6944: International test method for fire-resistant ventilation ductwork.

Discover the right fire-resistant duct solution for your project. Contact us for technical support and product information.