The Mayor's Ambient Noise Strategy - Greater London Authority

The Mayor’s Ambient Noise Strategy Mayor of London 221
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Responsiveness of the noise-maker to complaints;
‘Reputation’ of the noise-maker, including on matters wider than noise;
Relationship of the noise with traffic congestion, air pollution, safety
or other issues;
Economic and employment links between the recipient and the source
(e.g. people may be more likely to think the noise is justified if they
work there);
Characteristics of the neighbourhood, including mix of uses, or types
of housing, and attitude of recipient to it.
Activity engaged in by recipient.
State of health of recipient.
Experiencing environmental noise and vibration
Road traffic noise and vibration may be experienced in three ways:
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Airborne noise - generally the key issue, mainly from engines when
accelerating. Noise generated by interaction between tyres and the
road surface becomes dominant as speed rises.
Low frequency airborne sound, often from larger engines (especially at
low speed), can be mistaken for (structure-borne) vibration if it causes
windows, cups or other objects to rattle.
Vibration - ground-borne or structure-borne - is usually generated by
rapid changes in loading, as when vehicles pass over road surface
irregularities. In general, subsoils in London, and the types of road and
building materials used, mean that the city is not as vulnerable as
some other areas to true ground-borne vibration. Structural damage to
buildings as a result of ground-borne vibration from road traffic is
considered highly unlikely. 1 BS 6472: 1992 provides advice on
acceptable levels of vibration.
Rail traffic may be experienced similarly, although wheel-rail rolling noise
generally dominates, and heavy freight trains can cause distinct groundborne
vibration. True structure-borne vibration can result in ‘re-radiated’
noise (vibrating structural elements acting like loudspeakers) within
buildings (e.g. low rumble from underground trains).
Airborne road and rail noise is often screened from the listener by
buildings or landform. The height of an overflying aircraft means that it is
often the most distinct source in an otherwise quiet area. Higher
frequency sounds are attenuated more readily by atmospheric absorption
than lower frequencies. This may increase the tonality of noise from
overflying aircraft. The recipient’s response may be influenced by anxiety
about aircraft safety in general.