Fire suppression

The subject of fire suppression and mitigation in tunnels has always been contentious within the fire safety engineer community. “For many years hydrants and hose reels were provided for early intervention and the Fire Brigade dealt with surviving fires,” says Kidde Italia.

Kidde’s automatically-operated deluge system (Tunnel Fire Protection system – TFP), which uses low expansion foams produced by a specific agent (Tunnel Aqueous Film-Forming Foam, T-AFFF) was patented in 1999 by Silvani Antincendi and tested in the same year in the Piota Negra tunnel, in Switzerland, with the collaboration of the Swiss Fire Brigade.

Kidde says that analytical and numerical analysis, and the fire tests performed by the University Politecnico di Torino show that:

The system is able to slow down the fire growth phase, and to reduce the fire magnitude so that smoke generation and temperature levels are reduced

The system extinguishes class B fire sources such as a small petrol tanker with a heat release of 50-60MW and liquid pools with a 30-40m² surface area, and prevents their re-ignition

The system is able to mitigate and control class A fire sources such as a car and a van with heat release of 20MW.