HIGHWAY PLANNING AND HIGHWAY NOISE BARRIERS

Traffic noise from highways is a major source of annoyance. Planning of new highways and the upgrading of existing installations must incorporate the parameter of noise in highway design. This paper reflects, in part, the research conducted for the Transportation Research Board under a National Cooperative Highway Research Program project. Two fundamental aspects of highway noise are discussed: (1) assessment of the relative noise impact on the pollution exposed to alternate highway locations or designs and (2) control of highway noise through highway design. The assessment and control of traffic noise is presented in terms of the equivalent A-weighted sound level over a one hour time interval and the Day/Night Equivalent Level over the twenty-four day. These descriptors have been specified by the Environmental Protection Agency for environmental noise evaluation.