A noise map is the cartographic representation of the sound pressure (noise) levels recorded in a specific area during a specific period of time.

The usefulness of the noise map is to determine the population's exposure to environmental noise, in order to adopt the necessary action plans to prevent and reduce environmental noise and, in particular, when exposure levels may have harmful effects on human health...

There are two basic ways to approach creating a noise map:

1. By sampling. Through the acoustimemetric technique of spatial digitization through the use of sound level meters. It is the technique that has been commonly used when studying noise pollution in large areas or urban centers. The methodology is based on a campaign of direct noise measurements lasting no less than one year on gratings of certain sizes using a silver procedure.

2. By simulation. Currently, simulation techniques based on calculation are used, which shorten the duration of the data acquisition process and reduce its cost, in addition to introducing as a fundamental advantage the possibility of assessing what part of the captured sound comes directly from the source and what part comes from the different acoustic reflections "Reflection (sound)") of the environment. These new simulation techniques are possible thanks to the increase in the capacity of computer systems, the understanding and international standardization of the different ways that a source can generate a sound, the understanding of the effects of sound propagation through different media and materials (see image 1), and the standardization of calculation models. Through the use of these simulators, we can predict the noise levels that occur in any imaginable present or future acoustic scenario (see image 2).

The application of calculation methodologies allows us to differentiate noise sources and know to what extent each of them contributes to the sound level in each area of ​​an urban center. In this way it is possible to compare the relevance of each source in the noise pollution of the city and identify the variables on which action can be taken to reduce the impact of each of them.