Acoustic Associates use a variety of computer programmes to assist in modelling and mapping projects. This includes environmental computer modelling software IMMI.
These programmes are used to generate 3D noise maps.
Their advantage is that complex noise environments involving multiple sources (road, rail, aircraft and industrial/commercial plant) and over undulating terrain can be accurately modelled.
There are circumstances when it is helpful to have detailed information regarding noise propagation. At Acoustic Associates we use the computer based environmental modelling software IMMI.
This programme faithfully implements the guidance and methodology set out in ISO 9613: 1996: Part 2: Attenuation of sound during propagation outdoors – general method of calculation. This is the European Union standard calculation method for the propagation of sound outdoors.
As IMMI is a 3D acoustic modelling package, representations of noise impact at different facades and at different heights can be generated. From this information, specific glazing solutions can be provided which can differ due to the varying noise levels at different locations. By this means, accurate targeting of design solutions can be achieved, thereby reducing overall costs for a development.
In some circumstances, where there is a desire for assessing the introduction of noise mitigation measures such as noise barriers or earth bunding, noise modelling is the most cost effective solution.
Assessment of a site for it's suitability for residential development by modelling of the acoustic environment can often be invaluable. Models in this case can be used to generate design solutions to achieve suitable internal and external noise criteria in accordance with National Standards.
Introduction of new industrial noise sources near to residential properties have the potential to cause local residents to complain of noise nuisance and local authorities often ask for assessments to be carried out before granting permission for installing plant. Production of noise maps can be used to estimate the likely noise impact of new plant before installation based upon manufacturers' acoustic data. Further, in the case that proposed plant does not comply with local authority's requirements, this can be used as a tool to select an appropriate alternative unit or to determine the need for mitigation measures.