1、BRITISH STANDARD BS 7445-3: 1991 ISO 1996-3: 1987 Description and measurement of environmental noise Part 3: Guide to application to noise limitsBS7445-3:1991 This British Standard, having been prepared under the directionof the Environment andPollution Standards Policy Committee, was published unde
2、rthe authority of the Standards Board and comes into effect on 28 June 1991 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference EPC/1 Draft for comment 83/54418 DC ISBN 0 580 19734 4 Committees responsible for this British Standard The preparation of thi
3、s British Standard was entrusted by the Environment and Pollution Standards Policy Committee (EPC/-) to Technical Committee EPC/1, upon which the following bodies were represented: Association of Consulting Engineers British Broadcasting Corporation British Occupational Hygiene Society British Telec
4、ommunications plc Department of Health Department of the Environment (Building Research Establishment) Department of Trade and Industry (Air Division) Department of Trade and Industry (National Physical Laboratory) Engineering Equipment and Materials Users Association Health and Safety Executive Inc
5、orporated Association of Architects and Surveyors Institute of Acoustics Institute of Occupational Hygienists Institute of Physics Institute of Sound and Vibration Research Institution of Civil Engineers Institution of Electrical Engineers Royal Institute of British Architects Society of Environment
6、al Engineers Transmission and Distribution Association (BEAMA Ltd.) The following bodies were also represented in the drafting of the standard, through subcommittees and panels: Association of Consulting Scientists Association of Metropolitan Authorities Association of Noise Consultants British Ceme
7、nt Association British Coal Corporation British Forging Industry Association British Gas plc British Steel plc Department of the Environment Electricity Supply Industry in United Kingdom Engineering Industries Association Federation of Civil Engineering Contractors Institution of Environmental Healt
8、h Officers London Regional Transport Ministry of Defence Petroleum Industry Association Royal Automobile Club University of Salford Amendments issued since publication Amd. No. Date CommentsBS7445-3:1991 BSI 07-1999 i Contents Page Committees responsible Inside front cover National foreword ii 0 Int
9、roduction 1 1 Scope and field of application 1 2 References 1 3 Definitions 1 4 Specification of noise limit requirements 1 5 Checking compliance with limits 2 6 Presentation of results 3 7 Bibliography 3 Publication(s) referred to Inside back coverBS7445-3:1991 ii BSI 07-1999 National foreword This
10、 Part of BS 7445 has been prepared under the direction of the Environment and Pollution Standards Policy Committee and is identical with ISO 1996-3:1987, “Acoustics Description and measurement of environmental noise Part3:Application to noise limits”, published by the International Organization for
11、Standardization (ISO). ISO 1996-3 was prepared by Subcommittee 1, Noise, of ISO Technical Committee 43, Acoustics, with the active participation and approval of the UK. BS 7445 at present comprises the following Parts which have been published. Part 1: Guide to quantities and procedures; Part 2: Gui
12、de to the acquisition of data pertinent to land use; Part 3: Guide to application to noise limits. ISO 1999 is referred to in clause 0 for information only and does not affect the use of this standard. A British Standard does not purport to include all the necessary provisions of a contract. Users o
13、f British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-references International standard Corresponding British Standard BS 7445 Description and measurement of environmental noise ISO 1996-
14、1:1982 Part 1:1991 Guide to quantities and procedures (Identical) ISO 1996-2:1987 Part 2:1991 Guide to the acquisition of data pertinent to land use (Identical) BS 4196 Sound power levels of noise sources ISO 3744:1981 Part 4:1981 Engineering methods for determination of sound power levels for sourc
15、es in free-field conditions over a reflecting plane (Identical) ISO 3746:1979 Part 6:1981 Survey method for determination of sound power levels of noise sources (Identical) ISO 3891:1978 BS 5727:1979 Method for describing aircraft noise heard on the ground (Identical) IEC 651:1979 a BS 5969:1981 Spe
16、cification for sound level meters (Identical) IEC 804:1985 a BS 6698:1986 Specification for integrating-averaging sound level meters (Identical) a International Electrotechnical Commission. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 4, an
17、 inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.ISO1996-3:1987(E) BSI 07-1999 1 0 Introduction 0.1 ISO 1996 comprises the following three parts: P
18、art 1: Basic quantities and procedures; Part 2: Acquisition of data pertinent to land use; Part 3: Application to noise limits. 0.2 This part of ISO 1996 lays down guidelines for the ways in which noise limits should be specified and describes procedures to be used for checking compliance with such
19、limits. It is assumed that noise limits are established by local authorities according to these guidelines and are embodied in noise limit regulations to which reference is made. For certain types of sources of noise, more detailed procedures may be used, for example those specified in ISO 3891 for
20、aircraft noise. ISO 3891 is consistent with the requirements of ISO 1996. This part of ISO 1996 does not specify noise limits. Reference should be made to ISO 1999 for situations where noise may cause hearing impairment. 1 Scope and field of application This part of ISO 1996 lays down guidelines for
21、 the specification of noise limits and describes methods for the acquisition of data that enable specific noise situations to be checked for compliance with specified noise limits. 2 References ISO 1996-1, Acoustics Description and measurement of environmental noise Part1:Basic quantities and proced
22、ures. ISO 1996-2, Acoustics Description and measurement of environmental noise Part2:Acquisition of data pertinent to land use. IEC Publication 651, Sound level meters. IEC Publication 804, Integrating-averaging sound level meters. 3 Definitions For the purposes of this part of ISO 1996, the definit
23、ions given in ISO 1996-1 apply. 4 Specification of noise limit requirements 4.1 General Noise limits are specified in terms of equivalent continuous A-weighted sound pressure levels or rating levels during time intervals and at locations appropriate to specific noise sources and conditions. Noise li
24、mits may be set by national or local authorities on the basis of general considerations of compatibility with human activities and land use, taking into account the results of survey measurements, if available. Such limits may depend on many factors such as the time of day, the activities to be prot
25、ected, the type of noise source, and climatic, social and economic factors. Noise limit regulations have to comprise a number of basic elements which, in combination, define uniquely the circumstances under which compliance with the regulations can be verified. These elements are as follows: a) nois
26、e descriptor; b) relevant time intervals; c) the sources and their conditions of operation, where appropriate; d) locations where the noise limits have to be verified; e) meteorological conditions, where appropriate,; f) criteria for assessment of compliance with the limits. These elements are descr
27、ibed in more detail in 4.2. NOTEFor control and enforcement purposes, it may be appropriate to specify limits for emission by individual sources or group(s) of sources. 4.2 Specification of noise limits 4.2.1 Noise descriptors The preferred noise descriptor for the specification of noise limits is t
28、he equivalent continuous A-weighted sound pressure level or rating level during given reference time interval(s). If noise limits are specified in terms of rating levels, the procedures to be used for determining the levels shall be specified. Limits that apply to noise events may be specified in te
29、rms of sound exposure level. If additional limits are specified in terms of other descriptors, the procedures for determining such values shall be specified. NOTE 1For large-amplitude noise, such as the noise generated by sonic booms, mining or quarry blasts, measurements with C-weighting are used i
30、n some countries to determine the rating level. NOTE 2If it proves impossible to find locations where the noise from a source can be measured in isolation, limits may be specified in terms of the sound power level of the source. Methods for determining this quantity should then be specified (for exa
31、mple in accordance with ISO 3744 or ISO3746). 4.2.2 Relevant time intervals The reference time intervals shall be chosen to take into account typical human activities and variations in the operation of the noise source.ISO1996-3:1987(E) 2 BSI 07-1999 Noise levels from the source(s) under considerati
32、on may vary strongly at the locations selected. It may then be necessary to carry out measurements, during a number of reference time intervals, to establish a representative long-term average sound level or long-term rating level. The number of samples of the reference time interval required will d
33、epend on the range of variation. The long-term interval shall be chosen to take into account variations in source emission and sound propagation. For situations where variations of the received sound pressure levels are mainly determined by meteorological conditions, or where emitted noise varies in
34、 a complex manner, this time interval may be from one week to one year. 4.2.3 Sound sources and their operating conditions The source(s) to which the noise limits apply shall be specified, together with their conditions of operation. NOTESpecial noise limits may be specified for periods during which
35、 the source is known to emit unusual types or levels of noise, e.g. when the source is undergoing maintenance. 4.2.4 Locations The locations where the noise limits have to be met shall be clearly specified. They shall be appropriate for the measurement of the noise emitted by the source(s) under con
36、sideration. The height of the microphone above the ground shall be specified (seeISO 1996-1 and ISO 1996-2). If these locations are subsequently found to be unsuitable for measurement of the noise emitted by the source under consideration, additional positions shall be specified where such measureme
37、nts can be made (check points). Noise limits at the check points shall be derived from the levels specified at the initial locations. NOTEWhen specifying limits, the importance of certain transmission paths should be considered. This may be of special importance for establishing limits for indoor re
38、ceiver positions (e.g. transmission through open or closed doors and windows). 4.2.5 Meteorological conditions 4.2.5.1 General For outdoor transmission, changes in meteorological conditions may influence the received noise level if the distance between the source and the receiver is about 30m or mor
39、e. In such cases, the noise limits shall be based on an average value for either all relevant meteorological conditions or for specified meteorological conditions only. Since, for identical patterns of noise, the long-term average level will be different for the two cases, the noise limits should be
40、 fixed accordingly. Reference may be made to one of the two cases outlined in 4.2.5.2 and 4.2.5.3. 4.2.5.2 Averaging of levels for all meteorological conditions In this case, the noise limits refer to noise levels averaged for all relevant meteorological conditions. The measurements shall be made at
41、 times such that the results will be representative for the range of meteorological conditions for the site under consideration. The long-term average level may be calculated from the individual results, if required after weighting each result with a factor representing the fraction of the long-term
42、 time interval during which the corresponding meteorological conditions prevailed. NOTE 1Under certain meteorological conditions, it may be difficult to determine the specific noise of the source under consideration if there is insufficient difference between the levels of this specific noise and th
43、e residual noise. NOTE 2This technique has the advantage that it takes into account both variations due to meteorological conditions and variations in the source emission. 4.2.5.3 Determination of levels in specified meteorological conditions In this case, the noise limits refer to noise levels in s
44、pecified meteorological conditions. The meteorological conditions in which measurements are to be carried out shall be specified. NOTE 1The conditions specified will usually be those for which the noise levels at the locations where the noise limits have to be complied with are the highest. In this
45、case, the specified wind direction should form an angle of less than 45 with the direction from the source to these locations. Measurements during strong temperature inversions near the ground should, however, be avoided. NOTE 2Care should be taken to ensure that the specified meteorological conditi
46、ons cover all relevant source operating conditions. 4.2.6 Criteria for assessing compliance with limits In order to assess compliance with a noise limit, it will, in general, be necessary to consider the average of a number of measurements and their statistical distribution. Noise limit regulations
47、should indicate how this information should be used for assessing compliance with the limits. 5 Checking compliance with limits 5.1 Instrumentation The instrumentation and its calibration shall comply with the requirements given in ISO 1996-1. 5.2 Location of measurement positions Measurements for v
48、erification of compliance with noise limits shall be carried out at the positions and at the elevations specified in the noise limit regulations.ISO1996-3:1987(E) BSI 07-1999 3 5.3 Measurement time intervals and meteorological conditions Measurements shall be made over the time intervals and in the
49、meteorological conditions specified in the relevant noise limit regulations. 6 Presentation of results The results shall be recorded in a report of the investigation of compliance with noise limits, which shall include at least the following information: a) the relevant section of the noise limit regulations in question; b) the date and time of measurements; c) the location of measurement positions; d) the instrumentation used, details of its calibration and the types of analyses carried out; e) meteorological conditions during the measurements (wind dir
