2.5. Noise mapping calculations
The calculations to obtain acoustic maps require the demarcation of an area of calculation. After this step, the Predictor software generates a grid noise map whose distance between points on the grid is defined by the user. Grids of 15 × 15 m or 20 × 20 m generate acceptable approximations, with the advantage of greater processing speed, but may sacrifice some of the details of results in more densely populated areas. Thus, the grid size adopted here was 10 × 10 m. For maps of noise sensitive areas such as hospitals, the grid resolution was 2 × 2 m. The height of the grid was 4 m, as recommended by the Environmental Noise Directive [32].