Techniques for improved precision of environmental noise modeling

Environmental or outdoor noise models can produce results that are highly dependent upon a wide variety of factors. Even situations which appear to be straightforward can be subject to subtle influences which can significantly affect the modeling results. This paper covers several techniques that can be used to provide more precise results of outdoor noise models. Examples of lessons learned are also provided, along with a discussion of factors that should be included in each model and scenarios that require specific modeling techniques. These scenarios include time-varying effects, such as moving sources and changing topography, as well as indoor-to-outdoor sound propagation. The software package discussed in this paper is SoundPLAN, but the techniques described can be applied to other commercially available software packages for environmental noise modeling.