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Appendix 2 Summary of Current Technical Standards

1. DOMESTIC NOISE

No specific standards or codes of practice have been written for the purposes of giving guidance or an objective assessment methodology to assist officers investigating neighbour and neighbourhood noise.

Officers are left to extract guidance from an assortment of publications on other noise related topics. What follows is a synopsis of some of the sources.

These standards may be called upon to provide guidance for the judgement of what may be considered reasonable: it must be emphasised that they do not provide absolute criteria for deciding whether a noise is or is not a nuisance.

It is important in Scottish and English law that every case must be decided on its merits.

It is up to the competent person (normally an Environmental Health Officer) to determine whether a nuisance exists, in their opinion. It should be remembered that nuisance deals only with the unreasonable interference with the use of land or instances considered to be prejudicial to health.

In all cases, the local circumstances have to be taken into account and an assessment of reasonableness made. The EHO is the competent person who should act as an independent investigator and arbitrator in the matter.

1.1 BS 8233: 1999 Sound Insulation and Noise Reduction for Buildings: Code of Practice

This British standard is a code of practice that gives recommendations for the control of noise in and around buildings, and suggests appropriate criteria and limits for different situations. These criteria and limits are primarily intended to guide the design of new or refurbished buildings undergoing a change of use, rather than to assess the effect of changes in the external noise level.

Lower and upper design noise limits are recommended for 'good' and 'reasonable' conditions, the code of practice advises that "normally only the upper noise limit will need to be decided" (section 7.3). The noise is assumed to be steady and anonymous, such as that due to road traffic, mechanical services, or continuously running plant, and should be the noise level in the space during normal hours of occupation. The time period T should be appropriate for the activity involved (23:00-07:00 for bedrooms).

It should be noted that these noise levels relate to steady intrusive noise only, such as plant or steady road traffic noise; they cannot be taken to apply to music noise or intermittent events. A competent person (see Section 4.11) may consider measured noise levels below these levels to be a nuisance and conversely, may consider moderately higher noise levels not to be a nuisance, depending on the local circumstances.

1.2 Planning Advice Note PAN 56 "Planning & Noise" April 1999

The aim of this guidance is to provide advice on how the planning system can be used to minimise the adverse impact of noise without placing unreasonable restrictions on development or adding unduly to the costs and administration burdens of business.

The guidance, introduces the concept of Noise Exposure Categories ( NEC's) ranging from A-D to help authorities in their consideration of applications for residential development near transport-related sources.

1.3 BSENISO 140: 1998 (formerly BS 2750) and BSENISO 717-1: 1997 (formerly BS 5821: 1984).

These British Standards and European Norms relate to sound insulation tests of buildings and building elements. Testing of airborne noise insulation and impact noise insulation is covered. BSENISO 140 specifies testing in various situations and the necessary equipment to be used. Detailed recommendations for source and measuring positions and corrections for reverberation times are laid out. The corrected levels are then assessed against a set of standard curves to give a rating level ( BSENISO 717-1).

1.4 The Building (Scotland) Regulations, 2004

The Building (Scotland) Regulations are supported by a number of Technical Handbooks and are available in two volumes, for Domestic buildings and for Non-domestic buildings.

It was the intention that the Technical Handbook would be a level transfer of the technical requirements in the previous Parts of the Technical Standards. However certain recommendations concerning noise transmission have either been clarified, updated or become obsolete over the last few years and it was felt necessary to include these changes in the new technical handbook.

Performance values
Recommended performance values for separating walls and separating floors are given below. Tests should be performed after construction, using the procedures given in Annex 5.C of the Technical Handbook.

Airborne Sound (minimum values)
Minimum values of weighted standardised level difference (DnT,w), as defined in BSENISO 717-1: 1997:

Impact Sound (maximum values)
Maximum values of weighted standardised impact sound pressure level (L'nT,w) as defined in BSENISO 717-2: 1997

1.5 World Health Organisation Guidelines for Community Noise (1999)

The introduction to the WHO Guidelines gives the following scope for the document:

The scope of WHO's effort to derive guidelines for community noise is to consolidate actual scientific knowledge on the health impacts of community noise and to provide guidance to environmental health authorities and professionals trying to protect people from the harmful effects of noise in non-industrial environments. Guidance on the health effects of noise exposure of the population has already been given in an early publication of the series of Environmental Health Criteria. The health risk to humans from exposure to environmental noise was evaluated and guideline values derived. The issue of noise control and health protection was briefly addressed.

The Introductory chapter on Guideline Values notes that:

In the following, guideline values are summarized with regard to specific environments and effects. For each environment and situation, the guideline values take into consideration the identified health effects and are set, based on the lowest levels of noise that affect health (critical health effect). Guideline values typically correspond to the lowest effect level for general populations, such as those for indoor speech intelligibility. By contrast, guideline values for annoyance have been set at 50 or 55dBA, representing daytime levels below which a majority of the adult population will be protected from becoming moderately or seriously annoyed, respectively.

(Underlining, our emphasis)

In these Guidelines for Community Noise only guideline values are presented. These are essentially values for the onset of health effects for the general population from noise exposure. It would have been preferable to establish guidelines for exposure-response relationships. However, such relationships would indicate the effects to be expected if standards were set above the WHO guideline values and would facilitate the setting of standards for sound pressure levels (noise emission standards). Currently such exposure-response relationships cannot be confidently established, as the scientific literature is very limited. The best-studied exposure-response relationship is that between Ldn and annoyance ( WHO 1995a; Berglund & Lindvall 1995; Miedema & Vos 1998). Even the most recent relationships between integrated noise levels and the percentage of highly or moderately annoyed people are still being evaluated. The results of a forthcoming meta-analysis are expected to be published in the near future (Miedema, personal communication).

The guideline values are for the onset the health effect in the general population, the document goes on to state in paragraph 4.2.3 Sleep Disturbance Effects:

…Measurable effects on sleep start at background noise levels of about 30 dB L _Aeq.

…Where noise is continuous, the equivalent sound pressure level should not exceed 30 dBA indoors, if negative effects on sleep are to be avoided. When the noise is composed of a large proportion of low-frequency sounds a still lower guideline value is recommended, because low-frequency noise (e.g. from ventilation systems) can disturb rest and sleep even at low sound pressure levels. It should be noted that the adverse effect of noise partly depends on the nature of the source.

…If the noise is not continuous, L _Amax or SEL are used to indicate the probability of noise-induced awakenings. Effects have been observed at individual L _Amax exposures of 45 dB or less. Consequently, it is important to limit the number of noise events with a L _Amax exceeding 45 dB. Therefore, the guidelines should be based on a combination of values of 30 dB L _Aeq,8h and 45 dB L _Amax. To protect sensitive persons, a still lower guideline value would be preferred when the background level is low.

… Therefore, to avoid sleep disturbance, guidelines for community noise should be expressed in terms of equivalent sound pressure levels, as well as L _{Amax/ SEL} and the number of noise events. Measures reducing disturbance during the first part of the night are believed to be the most effective for minimising sleep disturbance.

1.5.1 Recommendations
The WHO document recommends the following:

In dwellings, the critical effects of noise are on sleep, annoyance and speech interference. To avoid sleep disturbance, indoor guideline values for bedrooms are 30dB LAeq for continuous noise and 45 dB LAmax for single sound events. Lower levels may be annoying, depending on the nature of the noise source. The maximum sound pressure level should be measured with the instrument set at "Fast".

To protect the majority of people from being seriously annoyed during the daytime, the sound pressure level on balconies, terraces and outdoor living areas should not exceed 55dB LAeq for a steady, continuous noise. To protect the majority of people from being moderately annoyed during the daytime, the outdoor sound pressure level should not exceed 50 dB LAeq.

At night, sound pressure levels at the outside façades of the living spaces should not exceed 45 dB LAeq and 60 dB LAmax, so that people may sleep with bedroom windows open. These values have been obtained by assuming that the noise reduction from outside to inside with the window partly open is 15 dB.

It is the job of the EHO as the competent person to assess whether a perceived nuisance is unreasonable, whilst the above gives some guidance, the following points should be borne in mind:

The WHO guideline levels have been set at the threshold of detectable effects in the population. A court of law may consider that this includes people who are more sensitive to noise than the average and so may regard the WHO Guideline values as not representative of the tolerances of the "normal" population (normal in this context can be regarded as having both its colloquial and statistical meaning). This is indicated by the setting of approximately 5 dBA higher values for 'reasonable' noise levels in BS 8233:1999, which post dates the initial publication of the current WHO guideline values.

The Court of Appeal has expressly stated that exceedance of the WHO Guidelines per se constitutes an actionable nuisance. All the other tests for nuisance still apply. WHO guidelines for Community Noise are exactly that, the individual case must be judged on its merit and noise measurements below WHO guidelines may be considered a statutory nuisance, conversely, noise measurements above WHO do not necessarily prove that a statutory nuisance exists.

1.6 NC and NR Curves

Noise Criteria ( NC) curves were developed in America as a means for specifying suitable noise levels for offices and other internal working environment. They are based on criteria of interference with speech communication and of annoyance and consist of a set of curves indicating sound pressure levels at various octave band frequencies. The shape of the curve is similar to that of equal loudness contours with levels highest at low frequencies decreasing progressively with increasing frequency. Subjectively less annoyance is caused by low frequency noise than that by a high frequency noise at the same sound pressure level.

To use NC curves, an octave analysis of the noise needs to be carried out and the levels plotted onto the curves. The NC value of the noise is the lowest curve, which is not exceeded by the plot. Comparison can then be made with recommended NC values that have been determined for different situations. (Recommended NC values for homes in suburban/rural areas are NC 20-25, and for urban areas is NC 25-30).

Noise Rating ( NR) curves are very similar to NC curves but are of European origin. They can also be used to evaluate a wider range of noise sources and be used for both indoor and outdoor situations, whereas NC curves are only intended for use indoors. NC and NR curves are particularly useful for dealing with noise from fans, ventilation and air conditioning systems when considering specifications for design purposes. (See Noise and Man, Burns: 1975, pl48-155).

Noise rating ( NR) is a graphical method for assigning a single number rating to a noise spectrum. Annex B of BS 8233:1999 discusses the use of NR curves and provides a method of calculating NR values.

Noise Rating ( NR) Curves are often erroneously referred to as ISO Rating Curves. The misconception arises out of the fact that this system of noise evaluation was placed before the International Standards Organisation in draft form in 1961 to be considered for ratification as an ISO recommended standard. They have not as yet been ratified and there appears to be some doubt as to whether they ever will be (Environmental Health: August 1973).

1.7 Constant Barking Can Be Avoided - Offering Guidance to Owners

This draft guidance was published as a consultative draft in June 2004. It sets out comprehensive advice on:

• Why dogs bark
• Why dog barking can be a nuisance
• Encouraging dog owners to co-operate
• Assessing the scale of the problem
• Measures to control the problem
• Directions for further help

The document is available to view at the Defra website.

2. COMMERCIAL NOISE

2.1 BS 4142: 1997 "Rating Industrial Noise Affecting Mixed Residential and Industrial Areas"

This standard is only concerned with the rating of the noise of an industrial nature, based on the margin by which it exceeds a background noise level, with an appropriate allowance for the acoustic features present in the noise. Its primary purpose is as a planning tool.

The document states in the Foreword that:

Although, in general, there will be a relationship between the incidence of complaints and the level of general community annoyance, quantitative assessment of the latter is beyond the scope of this standard, as is the assessment of nuisance.

The method described in the document requires the measurement or prediction of fixed equipment or plant noise (specific noise level) and a correction for the acoustic character and intermittency to give a rating noise level such that a comparison can be made between the rating level (predicted/measured and any relevant corrections) and the background noise level.

To assess the likelihood of complaints, the measured background noise level is subtracted from the adjusted rating level. (NOTE More than one assessment may be appropriate.) The greater the difference the greater the likelihood of complaints.

A difference of around + 10 dB or more indicates that complaints are likely.

A difference of around + 5 dB is of marginal significance.

If the rating level is more than 10 dB below the measured background noise level then this is a positive indication that complaints are unlikely.

Whilst this is not intended as a specific test for nuisance, the result could be used as background information to assess the expected likelihood of complaint if the general population were exposed to the same noise level.

2.2 BS5228 (1992/1997) - Code of Practice for the Control of Noise on Construction and Open Sites

This standard is approved by the Secretary of State under the provisions of section 71 of the Control of Pollution Act 1974 and consequently provides a definitive guide to the control of noise from construction and open sites, that Courts and planning inspectors give great weight. It consists of the following Parts:

Part 1. Code of Practice for Basic Information and Procedures for Noise Control (revised in 1997).

Part 2. Guide to Legislation for Noise Control Applicable to Construction and Demolition, including Road Construction and Maintenance (revised in 1997).

Part 3. Code of Practice for Noise Control Applicable to Surface Coal Extraction by Open cast Methods (revised in 1997).

Part 4. Code of Practice for Noise and Vibration Control Applicable to Piling Operations. (This Part is a revision issued in 1992).

Part 5. Code of Practice Applicable to Surface Mineral Extraction (except coal) Sites (1997).

The standard is a substantial document providing methods and data for predicting the noise and vibration levels to be expected from particular construction activities using a limited range of plant and equipment selected from the tables of data given for typical or specified circumstances.

Reference is made to the need for the protection of persons living and working in the vicinity of construction sites and other open sites, as well as for the protection of those working on the sites, from noise and vibration. It recommends procedures for noise and vibration control and aims to assist architects, contractors and site operatives, designers, developers, engineers, local authority environmental health officers and planners, regarding the control of noise and vibration. It draws attention to the provisions in the Control of Pollution Act 1974 relating to the abatement of nuisances caused by noise and vibration. The standard offers examples of good practice, although adherence to its guidance does not in itself confer immunity from prosecution.

2.3 "Study of Environmental Low Frequency Noise" - BRE 1994

This study recommends a protocol for investigation and measurement of Low Frequency Noise complaints based on research carried out by the BRE. Noise measurements should be carried out by use of frequency analysers with a minimum bandwidth of l/24 ^th octave, preferably in real time.

A standardised assessment under BS 4142: 1997 using the 'A' weighted scale may not be appropriate for the measurement of low frequency noise. It has however been suggested that a quick approximation can be obtained by comparison of 'A' and 'C' weighted measurements (Difference > 30dB - significant low frequency element - Noise Review Working Party BATHO Report).

A Review of Published Research for Defra on Low Frequency Noise and its Effects by Dr G Leventhall et al (May 2003) has recently been published. This study considers the properties of low frequency noise sounds, their perception, effects on people and the criteria that have been developed for assessment of their effects. The study is comprehensive containing approximately 200 authoritative references; the results of a simple survey carried out with respect to low frequency noise sufferers and provides recommendations for further research. See - www.defra.gov.uk/environment/noise/lowfrequency

2.4 BS 6472:1992 "Evaluation of Human Exposure to Vibration in Buildings"

This standard specifies a method for measurement and assessment of intermittent, impulsive and blast induced vibration. Weighting curves related to human response to vibration of buildings are provided. Consideration is given to the time of day and use made of the building under occupancy and guidance given on the magnitudes of vibration at which 'adverse comment' may be expected.

2.5 PAN 50 Annex A 'Controlling the Environmental Effects of Surface Mineral Workings' (1996)

The purpose of this guidance note is to advise minerals planning authorities (County Councils, unitary authorities) and the minerals industry on how the environmental performance of the industry can be improved by the control of noise from operations.

The guidance provides advice on how both planning controls and good environmental practice can be used to keep noise emissions to environmentally acceptable levels. Waste disposal operations share many common features with surface mineral workings and much of the advice contained in the guidance will be appropriate to the control of noise from waste disposal operations. Recommended noise limits are suggested which may form part of the conditions attached to any planning permission. At the time of publication of this guide MPG 11 is in the process of being reviewed.

2.6 Code of Practice on Noise from Audible Intruder Alarms 1982 ( DOE approved)

This provides guidance on the installation and operation of alarms to reduce misfiring and enable their disarming or deactivation with the minimum of difficulty. It suggests alarms be fitted with twenty minute cut off devices and that police be notified of key holders who can give access and deactivate continually ringing alarms.

In cases where nominated key holders are repeatedly unavailable or fail to act within the appropriate response time, or repeated false alarms happen, in Northern Ireland the local authority may use its powers under The Pollution Control and Local Government (Northern Ireland) Order 1978 to require the alarm holder to have an automatic cut out device fitted to the system. Para 5.2 of the Code of Practice calls for alarm installers and maintenance contractors to provide forms for use by key holders in notifying the police of nominated key holders, and in notifying the local authority of the installation of alarm systems or change in alar

2.7 Code of Practice on Noise from Ice Cream Van Chimes etc. 1982 (DoE approved)

This code gives guidance on the methods of minimising annoyance by noise from ice cream van chimes. The guideline deals with noise levels, the playing time of chimes, and their frequency of use in sensitive areas. The code does not create offences or have force in law but will be taken into account by local authorities and the courts in determining, amongst other things, the application of best practicable means.

2.8 National Farmers Union Code of Practice of Bird Scarers

This advises on the types of scarer available and alternatives to reduce the need for such devices. Recommended noise controls include use only between sunrise and sunset (not before 6.00 a.m. if sunrise is earlier), firing no more than four times per hour, liaison with other farmers, who may also be using them to limit the noise in any one locality, siting as far as possible from noise sensitive buildings and the use of noise absorbent shields.

2.9 Institute of Acoustics Good Practice Guide on Noise from Pubs and Clubs

In 1994, the (then) Noise Council surveyed members of its founding bodies and identified that there was a demand for a code of practice that would provide guidance on how to assess and deal with noise problems from pubs and clubs. The Institute of Acoustics ( IOA) then set up a working party comprising environmental health officers, acoustic consultants and, initially, members of the pub, club and entertainment industries to examine the issue. Objective noise level based criteria and performance standards have been dropped from the code although a "working draft on criteria, measurement, guidelines and other relevant information" was included in an annex to the last version of the draft guide. Defra has included criteria, measurement, guidelines for noise from pubs and clubs in its research programme for 2004/05.

3.0 RECREATION NOISE

3.1 Code of Practice on Noise from Model Aircraft 1982 ( DOE approved)

This deals with the legal noise control powers available and provides operating guidelines; including the use of mufflers; maximum recommended noise limits; times of operation; the numbers of model aircraft that should be operated simultaneously and the use of noise barriers and separation distances. It also specifies the method of measurement of noise emitted by model aircraft.

3.2 Clay Target Shooting - Guidance on the Control of Noise published by CIEH in 2003

This document is concerned with the ways in which shooting noise can occur and the methods to minimise or prevent annoyance and intrusion. It includes a recommended method for the measurement of noise and its subsequent rating that was produced by the BRE. The British Association for Shooting and Conservation and other shooting organisations do not support the use of this Code of Practice.

3.3 Code of Practice on Noise from Organised Off Road Motor Cycle Sport 1984

This Code of Practice was produced by the Noise Council in association with other organisations including Auto Cycle Union and the Amateur Motor Cycle Association. It advises on noise controls on enduro/ grass track racing, motocross, rallycross/ sand track/ trials/ trial cross and beach cross. Also specified are different maximum noise limits for machines competing in various types of event. The method of noise measurement has to comply with The Official Federation of International Motor Cyclist tests.

3.4 Code of Practice on Powerboat Racing and Water-ski Racing produced by the British Water Skiing Federation 1999

This code describes the main sources of boat noise and addresses the range of skiing disciplines at club and tournament level. It provides guidelines for minimising the impact of noise from water skiing on the surrounding community, including factors such as the noise output of the boats, course layout, hours of operation, the number of boats in use at any one time, screening of noise, the siting and use of public address systems, and how to control the effect of cars arriving at, and leaving from events. The maximum permissible noise levels from individual boats varies from L _Amax 75 dB for recreational, tournament and 'barefoot' skiing, to L _Amax 105 dB for international or world championship water ski racing events under specified noise measurement conditions.

3.5 Code of Practice for the Control of Noise from Oval Motor Racing Circuits 1996

The National Society for Clean Air and Environmental Protection ( NSCA) has published this Code of Practice, which aims to control noise from short oval raceways. It covers race cars such as stock cars/ bangers/ ministox and rods.

The code seeks to control noise in the following two ways:

i) by controlling noise from race cars and its attenuation by the fitting of exhaust silencers; despite the wide variety of vehicles racing on short oval tracks, tight engine restrictions mean that it is possible for the Code to stipulate a standard silencer for each type (formula) of race car. The only exception to this standard silencer policy is for the Formula One Stock Cars class, where there is no restriction on the engine type or size. For these cars, a noise level has been set and, as the RAC already has a noise level test technique in place at venues under its control, the Code adopts this as the control method for Formula One Stock Cars;

(ii) noise from other sources; the Code provides general advice on various techniques which can be used to control noise from the race site, including guidance on: site access and car parking location; the use of physical barriers; site layout; the positioning, orientation and number of public address loudspeakers; and times and duration of race meetings.

The Code also discusses the various legislative controls which must be observed when land is used for short circuit motor racing. Annexes to the Code contain a description of the sport of stock car racing, the various formulas of race car, silencer specification for these different types/ and contact details of relevant organisations.

3.6 Code of Practice on Environmental Noise Control at Concerts, published by CIEH in 1995

This code of practice addresses environmental noise control at concerts and similar large music events involving high powered amplification when held in sporting stadia, arenas, open air sites and within lightweight buildings. Various guidelines and criteria are described. The code is not designed to address the question of environmental noise arising from discotheques, clubs and public houses.

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