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#MODEL NOISE WITH DIRECTIVITY IN CADNAA SOFTWARE#
#MODEL NOISE WITH DIRECTIVITY IN CADNAA ISO#

CadnaA (Computer Aided Noise Abatement) is the leading software for calculating, presenting, evaluating and forecasting environmental noise in industrial and civil environments. is now equipped with the new CadnaA calculation code. Wikimedia Commons has media related to Noise exposition maps.TECSA S.r.l.

UK Department for Environment, Food & Rural Affairs: Noise Mapping England.

The consultant can evaluate the effectiveness for decisions in action plans, in order to minimize noise.Įxamples for software packages used for noise mapping are: Simulation tools are very useful specially at planning stages, where measurements are not possible. The creation of a good acoustic model can be quite complicated. To calculate the noise propagation, it is necessary to create a model with points, lines and areas for the noise sources. Although some databases can be found, in some cases it is necessary to make measurements (ISO 3740) for describing the source. Measurements are used for the validation of results.įor industrial noise map production, the most important thing is the description of noise sources: sound power levels (emission), directivity, working periods. The main challenges for the acoustic consultant include the collection of data, creating useful models of the street network and a good digital terrain model (DTM).įor train and road traffic noise, the description of the sources is usually made in terms of parameters such as speed, number of vehicles etc. Today the use of software packages has made the process easier, but the accuracy of results depends on the quality of input data.

#MODEL NOISE WITH DIRECTIVITY IN CADNAA ISO#

Some of them use empirical models (for instance, INM for airport noise mapping), but most of the models are based on the physics of propagation of sound outdoors (defined in ISO 9613).

There are several methods for making noise maps. Facade sound levels must be calculated or estimated from the previous map. With a strategic noise map, furthermore, an evaluation is possible to show the number of people exposed within dBA ranges. The maps may be useful for planning stages, or for prior evaluation of action plans, or determination of most polluted areas. According to the END five dBA ranges are used for this contour (isoline) representation. When results are obtained, using GIS tools, spatial interpolation must be applied in order to give a continuous graphical representation of sound levels. Using either approach, a grid of receivers must be defined in order to measure or calculate noise levels. Computation methods are widely preferred, because of the large amount of yearly averaged locations required. The result can be determined by computation or measurement methods. All of these indicators may be defined in terms of A-weighted decibels (dBA, dB(A)). The main noise indicators for noise mapping are long-term averaged sound levels, determined over all the correspondent periods of a year. This map can be used for scientists, politicians or other interested parties. The term 'strategic' is very important in this definition, because the management of environmental noise must be made for the long-term. The main goals of the END are to make a diagnosis of noise pollution in Europe that can lead to noise management plans and acoustical planning.

Strategic noise map shall mean a map designed for the global assessment of noise exposure in a given area due to different noise sources or for overall predictions for such an area."ĮU Member States are required to produce strategic noise maps in their main cities, near the main transport infrastructure and industrial sites. " noise indicator shall mean a physical scale for the description of environmental noise, which has a relationship with a harmful effect Although some previous approaches had been made, the main international agreement and definitions for noise mapping were born in relation to the Environmental noise directive of the European Parliament and Council (Directive 2002/49/EC of 25 June 2002, commonly referred to as the END).