A European Directive means central government must be able amongst other things to provide noise mapping.
Gascinating site: http://noisemapping.defra.gov.uk/wps/portal/noise/maps

Excessive noise is a serious pollutant which results in serious educational problems – people can’t concentrate with such noise around them.

It shows in East Dulwich that two of our primary schools Goose Green and St.Antony’s borders roads with noise issues. Fortunately St.Antony’s is more set back and probably no more affected than Heber or Goodrich.

Take a look.

30dB (decibels is a conversation in a private room), 55dB or above and people inside rooms will start to be seriously disturbed.