Gregory A. Miller
Mech. Eng. Dept., The Cooper Union for the Advanced of Science and Art, Cooper Square, New York, NY 10003-7183
Daniel R. Raichel
The Cooper Union and the Graduate Center of the City University of New York
The problem of urban noise pollution can almost be considered as an architectural acoustics problem. City blocks are treated in a manner mathematically analogous to the acoustics of rooms. Six New York city blocks were selected---chosen for their varying geometries, materials, and traffic patterns---and measurements of L[sub eq] were taken during one-hour periods using a type 1 sound level meter. This is an experiment in progress with even more data to be accumulated for further refinement of the theory. The sound levels produced by various sources in these blocks are found by measuring average traffic flow, pedestrian traffic, etc. Predicative noise level equations (based on the sound level from a point source) are being generated on the basis of the physical characteristics of each block, and will be reconciled with experimental data to formulate characteristic equations that should accurately predict the sound pressure levels which observers are subjected to. It is anticipated that the alteration of the absorption coefficients of the structures lining the blocks will constitute the major factor within the reconciliation. The results of this experiment can in time be used to encourage wiser materials choices and more careful planning in future urban development.