What about the sounds produced by so-called boom-cars which are traveling, pulsing noise factories? What about uncomfortable sound levels at concerts, theaters and public sporting events? What about the sound of slow train horns in urbanized areas or the morning noises accompanying garbage collection? What about all the noise on our streets contributed to by buses, trams, car horns, car alarms, motorcycles and unsound-proofed exhaust systems? What about the risks to children from noisy toys and personal sound systems? What about the noise of barking dogs, leaf blowers and RVs? What about the noise of low-flying planes? In general, sounds that we deem unwanted or unnecessary are considered noise. Our society is plagued by noise, which is intrusive, omnipresent and omnipresent; most importantly, it's unhealthy. Most reasonable people would agree that much of the ambient noise we are subjected to has no use and is therefore unwanted. The variety of noise-polluting devices and activities is great and seems to be growing day by day, although there is no consensus on what is useful and desirable or what is polluting and noise-causing..