The inferno that engulfed a freeway tunnel north of Los Angeles after a pileup that killed three people in October 2007 showed their ferocity. About 300 firefighters battled the blaze throughout the night. Click here.
With an increase in both the number of tunnels and the vehicles that use them, more attention than ever is being paid to tunnel fire safety. The way firefighters tackle and are warned of such fires could change drastically in the coming years thanks to advances in technology.
Canadian-US study
A major two-year research project in the United States and Canada that studied the effectiveness of existing fire detection technologies in tunnels came to a close in November. The Fire Research Program at Canada's National Research Council was joined in the project by the Institute for Research in Construction and the Fire Protection Research Foundation of the US. Visit http://irc.nrc-cnrc.gc.ca/fr/index_e.html and www.nfpa.org/categoryList.asp?categoryID=242&URL=Research%20&%20Reports/Fire%20Protection%20Research%20Foundation&cookie%5Ftest=1
The main idea of the study is to look at some of the strengths and weaknesses of the various different types of systems and what can affect their performance. Although there has been a lot of tunnel fire research done in Europe and some in the US, there has been very little done on the performance of detection systems.
The study focused on five main technologies that can be used in tunnels to detect fires: linear heat detection systems, flame detectors, CCTV visual fire detectors, spot heat detectors, and smoke detection systems. The results of the study will be used to update NFPA 502 standard for road tunnels, bridges, and other limited access highways.
The study will also help manufacturers and authorities decide which type of detection system is best suited to any given tunnel. It has been broken down into three areas - laboratory testing, field testing and computing modelling - in order to get the best results.
For the laboratory testing, researchers are using the National Research Council's state-of-the-art facilities in Ontario, where a model of a tunnel, about 10 m wide and 40 m in length, has been built. In addition, tests have also been conducted in real, working tunnels in Montreal and the Lincoln tunnel in New York. Finally, computer modelling work has been done to bring the results of the first two series of tests together and provide hypothetical scenarios.
The study was vital in improving fire safety in tunnels, and therefore firefighter safety, because of the increase of vehicles on the roads using existing tunnels and the trend of building more tunnels to improve transport links.
There is an increase in truck size, and using trucks is also becoming a more economical way to transport things. There are also more tunnels, as they are seen as a way to create more roadways without making it too crowded on the surface.
LUF60
The giant strides in fire-related technology are not limited to tunnel detection systems. In 2007, four departments in Virginia became the first in the US to acquire a LUF60, a mobile remote controlled firefighting machine that helps extinguish fires in confined areas such as tunnels.
The unit, which has a high capacity positive pressure ventilator and a "water beam" fog, clears the path for advancement of a distance of up to 300 metres. It clears away smoke and toxic gases and reduces the fire's intensity, allowing firefighters to tackle the blaze more safely. It can literally control the atmosphere within the tunnel, so firefighters can get to the fire. It pushes all the heat and smoke away, so the firefighters can get close to the seat of the fire and then use conventional means to put it out.
The Newport News Fire Department, one of the departments in Virginia to have acquired the machine in January 2007, has yet to operate it in a real scenario, but has used it in training. The LUF60 is distributed in the US by Singer Associates Fire Equipment. Visit www.luf60.com 04/08.
the LUF 60 gets a workout dealing with a tunnel fire at a test tunel in Austria
Testing took place at the National Researcg Councils facilities in Ontario in 2007
