FAQs
1. Noise Mapping general
What is noise?
Noise is unwanted sound and sound in any variation in atmospheric pressure that
the ear can detect. For the ear to detect the variation as sound it has to occur
at least 20 times per second. It is very subjective – what is noisy for one person
may not bother someone else. Noise is measured in decibels on a logarithmic scale
(a bit like the Richter scale for earthquakes). To get an idea of how loud noise
is at any particular level, have a look at the NSCA site
NSCA
What is a noise map?
A noise map is rather like a weather map for noise but it shows areas which are
relatively louder or quieter. Just as a weather map might have isobars joining points
of equal air pressure, a noise map can have contours joining points having the same
noise level.
How are the noise maps produced?
Noise maps are produced by computer software that calculate the noise level at a
specific point as it spreads out from the sources of noise that have been included.
The software can take account of features which affect the spread of noise such
as buildings and the shape of the ground (e.g. earth mounds), and whether the ground
is acoustically absorbent (e.g. fields) or reflective (concrete or water).
What are the noise maps for?
Noise maps have two main purposes. Firstly, they can be used to find areas where
noise levels are high and these can be linked to population data to estimate how
many people are affected. This leads to the second use – and the main point of noise
mapping – to help in the production of noise action plans to manage noise and reduce
noise levels where appropriate.
2. Noise Maps published on this site
What noise mapping has been undertaken?
As required under the European Environmental Noise Directive we have mapped major
roads which have more than six million vehicle passages a year, major railways which
have more than 60,000 train passages a year, major airports with more than 50,000
movements and transport sources and industry in agglomerations (large urban areas).
Does this site include noise maps for the whole of the UK?
This site includes maps for Scotland only. The site will be updated to include links
to England, Wales and Northern Ireland when the sites become available.
Has noise mapping been undertaken in the past?
Although noise mapping has been undertaken, in one form or another for many years
the use of the technique for strategic mapping is a relatively new concept in the
UK. The first comprehensive noise maps for a major UK city was the Birmingham Noise
Map which was completed in 1999. The London Road Traffic Noise Map was completed
in 2004. In Scotland we have learned from these projects before producing the Strategic
Noise Maps.
When and how often will the noise maps be updated?
A five-yearly rolling programme will continuously review new data and whether it
is suitable to be incorporated into the mapping process. The noise maps will be
updated every five years as required by the EU Directive.
Do noise maps show how noisy it is where I live?
In the agglomeration (urban areas) maps you can search down to postcode level. Bear
in mind that the models show an average noise level for an average day in the year
calculated on the basis of a 10m grid a height of 4m above ground level. The maps
are strategic and should be used accordingly.
Can I pass a copy of the map to my insurer?
The noise map has not been developed to be a definitive assessment of risk for point
locations or individual properties and is therefore not suitable for insurance purposes
or property enquiries.
What is an agglomeration?
An agglomeration is a large urban area with a population of over 250,000 and a population
density of more than 500 persons per square kilometre. The agglomerations we have
mapped in this round are:
Glasgow and Edinburgh
You can see the maps of the agglomerations here.
Please note the agglomerations do not match local authority boundaries.
Are the airport maps the same as published on other websites?
Glasgow, Edinburgh and Aberdeen airports have noise maps produced by the Civil Aviation
Authority. These are produced using Leq,(16hour) rather than Lden It must be remembered
that the annual average Lden indicator is different from the summer average 16 hour
LAeq indicator that has traditionally been used to describe the noise exposure from
the airport. Thus the two sets of results must not be compared. Instead they should
simply be seen as two methods of describing average noise exposure at the airport.
The END requires the maps to represent the annual average values. This contrasts
with the common UK practice of producing aircraft noise contours for the average
summer’s day.
How is Population Exposure calculated?
Population exposure is calculated using a Geographical Information System (GIS),
a methodology is developed whereby measures of noise exposure and population, ethnicity,
and socio-economic characteristics are calculated for defined areas.
How were the maps made?
The maps are made by created by computer analysis using the specialised software.
This calculates the noise level on a 10m grid at a reception height of 4m as required
by the Regulations. The data required for the calculations of noise levels have
been determined by consultation with various organisations including Transport Scotland,
SEPA, Network Rail, British Airports Authority, Local Authorities, and others.
The software takes account of physical features such as buildings and the ground
contours. The grid information is then calculated is then used to create the series
of noise contours bands a shown drawn in the noise maps.
How accurate are the maps?
The maps are produced using computer based three dimensional noise models. This
process requires the acquisition of information about the noise source and the path
of propagation.
The noise maps are produced for use at a strategic level and are likely to give
an acceptable level of accuracy for these purposes. A the predicted noise levels
are based on a 10m calculation grid at a height of 4m above ground level they will
not however represent every situation at a local level and it is likely that more
detailed examination will be necessary in some of these situations in order to develop
local action plans.
Who has produced the noise maps?
The noise maps have been produced by Hamilton McGregor (Hamilton & McGregor Consortium)
on behalf of the Scottish Ministers.
I find the concept of what roads have to be mapped and when confusing can you explain
further?
For first round mapping the roads to be mapped are essentially motorways and A roads
having more than 6 million passages per year, as well as all roads within the “agglomerations”
of Edinburgh and Glasgow which exceed the qualifying flow of 1000 vehicles or more
per day. For the second round of mapping in 2012 the roads to be mapped are essentially
motorways and A roads having more than 3 million vehicle passages per year as well
as all roads within the agglomerations of Glasgow, Edinburgh, Aberdeen, Dundee and
Falkirk/Grangemouth. The actual roads and railways to be mapped will be subject
to finalisation based on the most up to date data available at the time. For example
if the population of Falkirk Grangemouth were to drop by 2012 there would be no
requirement for mapping the whole agglomeration. Similarly for rail the first round
railways are those having more than 60,000 train passages per year as well as all
rail within the agglomerations of Edinburgh and Glasgow. The second round railways
are those with more than 30,000 train passages per year as well as all railways
within the agglomerations of Glasgow, Edinburgh, Aberdeen, Dundee and Falkirk/Grangemouth.
3. Noise Mapping and Action Plans
How will action plans be developed?
Action plans will be developed as follows:
- Analysis of the strategic noise maps. This should include population
exposure information that requires to be sent to the commission in December 2007.
This will allow identification of candidate areas for noise management areas.
- Further investigation and analysis of the candidate areas that
could include noise measurements but will involve checks on the ground to ensure
that the assumptions underlying the strategic maps are reflected at the local level.
(For example the strategic maps may show high exposure levels but there may have
been physical changes on the ground since the data was collected). More simply there
may also be some inaccuracies in the maps as they are strategic maps after all.
- A review of existing UK, Scottish and Local policies, plans and
programmes that may have an impact on the strategic environmental noise climate
for the areas identified as potential noise management areas. (e.g. transport plans
and programmes, local plans, air quality management plans.
- An evaluation
of potential mitigation measures to manage noise, with options subject
to a cost benefit analysis. This could include identifying gaps in existing policies
and plans with recommendations to fill those gaps as appropriate.
Further information on the draft guidance on action planning, and the opportunity
to feedback on the draft guidance on noise action plans can be found here.
What will action plans contain?
Action plans will contain information and guidance relative to the process whereby
environmental noise, as described in the Regulations, will be managed. It will involve
the provision of information, consultation, and ultimate decision making on the
issues of noise management
What about quiet areas?
The Directive requires action plans for agglomerations to include measures which
aim to protect quiet areas against an increase in noise. The regulations require
that Quiet Areas within agglomerations are identified. What does quiet mean? The
Transport Research Laboratories (TRL) undertook
research for Defra on the subject of Quiet Areas. The research reported
that defining, identifying and appreciating the benefits of preserving quiet or
relatively Quiet Areas in urban conurbations cuts across many different fields including
health, physical and psycho-acoustics, environmental psychology. An important aspect
of the research carried out into Quiet Areas has been to establish the positive
effect natural sounds have on health and well-being.
Lists of Quiet Areas will be included in agglomeration action plans.
What are consolidated noise maps?
The term ‘consolidated’ in this context means a map showing the total noise level
at a location from the various sources being mapped. The consolidated maps, as requires
by the Regulations is the combination of the noise maps for each of the road, rail,
industrial and aircraft maps within the agglomerations. The consolidated maps are
produced simply as a logarithmic sum of the separate source sound levels and are
not subject to response or effects based corrections in any shape or form. It is
important therefore to remember that any differences in community response between
the different noise sources present at the same sound should only be interpreted
in that light.
4. Noise general
For an explanation of the noise terms used please click here.
Why not measure the noise?
The European Commission’s advisory group on environmental noise recommends that
Member States use computer modeling rather than measurements.
There are several technical and practical reasons why noise maps are normally produced
using computer predictions rather than from actual noise measurements. To produce
a map based on measurements would require many measurements to be taken over long
periods and this would have been prohibitively expensive. In most cases, the noise
at a location is produced by a combination of different sources. These might be,
for example, a mixture of, say, roads and railways. Normal noise monitoring cannot
distinguish the contribution from each of these different sources and so noise action
planning – deciding which source or sources to tackle to reduce the overall noise
level – is not straightforward. Noise maps produced by computer prediction can be
used to show the noise from individual sources.
Noise measurements can also be affected by the weather in several ways. Firstly,
the source itself might be affected, traffic noise for example has a different characteristic
when the road surface is wet and the direction of take-of at an airport might be
affected by the wind direction. Secondly, the measuring equipment can itself be
affected – high winds can generate noise on the microphone. Finally, high winds
and heavy rain can themselves be sources of noise from their action on trees and
buildings surfaces and these can affect the levels of measured noise. Weather conditions
therefore impose a real constraint on the number of days (or nights) when measured
noise levels can be relied on.
What can I do about noise?
Remember the regulations apply to noise from road railway and airport sources, as
well as industrial noise. The regulations do not apply to noise that is caused by
the person exposed to the noise, noise from domestic activities, noise created by
neighbours, noise at work places, or noise inside means of transport or due to military
activities in military areas.
Noise from domestic activities or noise created by neighbours can be dealt with
under the Environmental Protection Action 1990 and Antisocial Behaviour etc. (Scotland)
Act 2004. Part 5 of the Antisocial Behaviour etc. (Scotland) Act 2004 contains provisions
in relation to noise nuisance and in particular gives local authorities additional
powers to deal with noise nuisance and tackles the problems of night noise in dwellings.
Noise exposure at work is governed by the Control of Noise at Work Regulations 2005
and noise from construction site is controlled by the Control of Pollution Act 1974.
Further information on the legislation referred to here can be obtained from
http://www.scotland.gov.uk/about/ERADEN/EcolAU/00017824/nlr_rpt.pdf
Details of Draft Noise Management Guide Guidance on the Creation and Maintenance
of Effective Noise Management Policies and Practice for Local Authorities and their
Officers in Scotland can be obtained from
http://www.scotland.gov.uk/Resource/Doc/77843/0018687.pdf
With regard to the noise covered by the regulations, i.e. transportation and industrial
noise the best way to get involved is to comment on the action plans being produced
for your area. These will go out to public consultation and you will have a chance
to have a say in the action planning measures. To offer feedback on the noise action
planning please click here.
How do I complain about noise?
Information on how to complain about noise is provide here and here.