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No warranty or guarantee applies to this software, and therefore any users should satisfy themselves that it meets their requirements.
This model implements most of the procedure detailed in the Calculation of Road Traffic Noise (CRTN - ISBN 0 11 550847 3) issued by the Department of Transport in 1988. The aim has been to provide a basic platform for calculating road traffic noise levels for non-complex situations. The model is limited where for example; a separate calculation will be needed to take account of any complex arrangements of reflecting surfaces, as only a simple reflective correction is implemented here. Where consideration is to be given to situations where low traffic flows occur, it will be necessary to make specific reference to CRTN. In such cases, a further correction is generally needed, which is not implemented here. Copies of CRTN are available from The Stationery Office.
The results from this calculation method may now be converted to the new EU noise indices. Please see the DEFRA website for further information.