Blue, Green, Red Contours.

This is a clear visual indicator of the variation in noise levels over an area, with red being the noisiest, and blue being the quietest areas.

ISO 1996 5 dB Steps

The ISO 1996 specifies the colours to be used in noise mapping in either 5 or 10 dB steps. This is good for presentation as it gives consistency, but it may not give sufficient resolution for some applications.

Planning Policy Guidance Note 24

This enables areas to be mapped according to which PPG24 caegory they would full into for planning applications. This is a very useful tool for those involved in urban planning and design, and local authority environmental health officers assessing applications.