Bhubaneswar, Jan. 25 -- Bhubaneswar is a relatively quieter city jungle than many others of its ilk - in size and vulnerability. But the sound of the city is getting shriller and coarser. The whole of Odisha's mobile population is pumping into the place every day. This population is both upwardly and downwardly mobile. The number of vehicles on the road has surged by more than 20 times in the last two decades. With more than a million vehicles, the road traffic noise environment is getting worse. Individual contribution to environmental noise by the air horn of different motor vehicles has been assessed by some groups. The episodic and impulsive noise levels of different types of vehicles were found to be higher than the 70 dB traffic noi...