| THE LEGISLATIVE OR REGULATORY FRAMEWORK
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| Please list all relevant laws, enactment's, standards etc. (where possible giving information about how they interrelate) |
The Environmental Protection Act 1990 allows for industrial noise to be assessed as a statutory nuisance if the circumstances so dictate. Industrial noise can also be assessed as a private nuisance under common law. There is no noise limit value to help in deciding whether industrial noise is a nuisance or not. |
| NOISE LIMITS (where stated) |
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What noise limits are used ? Please give details of these in terms of
- how and where they are specified
- metric used
- day and night limits
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There are not industrial noise limits in the UK. BS4142:1997 provides a technical means of assessing whether or not 'complaints are likely'. The result of an assessment carried out to BS4142 would normally be relevant to the deliberations of any court considering whether or not a nuisance exists. |
| Is the assessment of noise against the limits based on measurement, prediction or both ? |
Noise levels are determined by measurement, but calculations are permitted where they can be justified. |
DERIVATION OF NOISE LIMITS
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| Please give summary details on the basis of these noise limits e.g. on which research findings and/or practical considerations |
The derivation of the method of assessment in BS4142 is technically obscure. It appears to be based on an early USA report by Rosenblith and Stevens dating from 1955, with various modifications introduced by different British Standards Committees over the years. |
| Is further research planned or considered necessary ? |
Various research programmes have been carried out in recent years in support of the technical improvements to BS4142, further work appears to be justified. |
| THE LEGISLATIVE OR REGULATORY FRAMEWORK
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| Please list all relevant laws, enactment's, standards etc. (where possible giving information about how they interrelate) |
Town and Country Planning Act 1990. Planning Policy Guidance Note PPG24 : Planning and Noise. PPG24 provides general guidance and advice on the aspects to consider when dealing with planning applications for new development where dwellings may be subject to noise. The noise exposure categories in PPG24 are used for new dwellings near existing noise sources. |
| NOISE LIMITS (where stated)
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What noise limits are used ? Please give details of these in terms of
- how and where they are specified
- metric used
- day and night limits
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Noise exposure categories (NECs) are used to determine the degree to which noise is a factor in the planning process, based on LAeq,t :-
- Noise need not be considered as a determining factor in granting planning permission, although the noise level at the high end of the category should not be regarded as a desirable level.
- Noise should be taken into account when determining planning applications and, where appropriate, conditions imposed to ensure an adequate protection against noise.
- Planning permission should not normally be granted. Where it is considered that permission should be given, for example because there are no alternative quieter sites available, conditions should be imposed to ensure a commensurate level of protection against noise.
- Planning permission should normally be refused.
A B C D
0700 - 2300 <57 57 - 66 66 - 72 >72
2300 - 0700 <48 48 - 57 57 - 66 >66
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| Is the assessment of noise against the limits based on measurement, prediction or both ? |
Both: measurements allow noise contour maps to be made, and position allows prediction of noise at buildings |
| DERIVATION OF NOISE LIMITS
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|
| Please give summary details on the basis of these noise limits e.g. on which research findings and/or practical considerations |
Builds on the principles of Planning Circular 10/73 and the recommendations made by the Noise Review Working Party 1990. The boundary of NEC A and B for daytime levels is based on considerable research using local surveys and measurements which show that 57dB(A) LAeq (previously 35 NNI) relates to the onset of annoyance. Night time levels are taken from WHO Health Criteria 12 "based on limited data available, a level of less than 35dB(A) is recommended to preserve the restorative process of sleep". This is corrected from internal to external free field noise levels by adding 10dB(A) for the attenuation of an open window and corrected by a further 2dB(A) for reflections from the ground. 48dB(A) is the nearest aircraft LAeq contour level. The boundary of NEC B and C for daytime levels is based on the trigger level for official grant schemes of 66dB(A) LAeq,16h (previously 50 NNI) at Heathrow, Gatwick and Stansted airports. Night time levels are based on the trigger level for official grant schemes at Stansted of the 57dB(A) LAeq noise contour value. The daytime boundary of NEC C and D is based on a well established level proposed in Planning Circular 10/73 of 60 NNI, equivalent to 72dB(A) LAeq,16h with a 2dB(A) allowance for ground reflection included. Night time levels are based on the WHO limit of 35dB(A) with an allowance for the typical attenuation of the standard noise insulation package and corrected to free field. A further reduction of 1dB(A) ensures levels are below 35dB(A) indoors giving a corresponding nearest noise contour of 66dB(A) Leq. |
| Is further research planned or considered necessary ? |
LAeq16h maps being produced to replace NNI ones |