Emissions of noxious supstances in road tunnel

Construction of tunnels, galleries, bridging objects and other underground engineers constructions is the most exacting work at low buildings. \nTunnel seems to be very simple building but there must be interdisciplinary interweaving of entire civil engineering knowledge of geology, mining, architectures, ecology and of other in all phases of planning, building and maintenance of underground constructions. \nTunnel is only one of the objects on a road. Careful planning of traffic only through tunnel won't have regular effects when the facts are limited only to tunnel. The traffic must be planned on wider influential area of tunnel to avoid the traffic jams and other situations in tunnel, which can result in emission concentration in and out of the tunnel. In accordance with legislation the influentially range of streets must be defined by traffic studies and estimation of impacts on environment. Therefore the regime of traffic and signaling must be changed in chase of extraordinary accidents to avoid the undesirable situations in the tunnel. \nAt the end of the year 2007 there were 23 tunnels, galleries and covered dugs on Slovene highways, common length of 34.125 meters. The longest tunnel with only one pipe is the Karavanke tunnel in length of 7.864 meters. The longest two pipes tunnel is called Trojane (2.931 meters). \nWe have to mention the Šentvid tunnel, which will connect northern and west highway with Ljubljana road circle. The new tunnel is very close to very densely populated district. \nThe characteristic for all tunnels is that the emissions of gases from engines with internal combustion are concentrated, that means the allowed and limited values inside or outside the tunnel pipes are many times exceeded. This is very big problem in case of the immediate neighborhood of bigger settlements.