CMS to improve underground fire-fighting system

The High Expansion Foam System is the last line of defence against fire in the CMS cavern


CMS has many different safety systems installed in the underground experimental area. These are designed to protect the detector and all the associated electronics as well as the cavern itself. In case of fire, the last line of defence is the High Expansion Foam System.

Following the fire of 1999 in the Mont Blanc tunnel, CMS acknowledged that, as a similar deep-underground facility, it needed an extinguishing system that can be operated remotely, is completely passive (does not require pumps or electricity), can cope with a big fire in the cavern and, lastly, does not need the specialist intervention of fire fighters to be operated. The foam system was installed in 2006, with an Italian company called Kiddie Italia providing the components and ZEC, a Polish company, setting up the piping. The system is completely passive, relying on a 100 m water column between the surface reservoir and the underground cavern to provide the necessary pressure. In five minutes, 20 m3 of water mixes with foaming liquid to transform into 16,500 m3 of foam that fills the entire cavern.

Read more:CMS to improve underground fire-extinguishing system” – CMS