1、Designation: E1780 12Standard Guide forMeasuring Outdoor Sound Received from a Nearby FixedSource1This standard is issued under the fixed designation E1780; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis is one of a series of standards and guidelines for measurement and evaluation of communitynoise. Techniques and precautions in
3、this guide are not fixed or mandatory and cannot replace thejudgment of acoustical professionals. Rather, this guide is a summary of processes found to beproductive and useful in ensuring that meaningful information will be gathered in an efficient mannerabout fixed sources of noise in a community a
4、s they each may exist. Others in this series include GuideE1014, which covers manual A-Weighted measurements of outdoor noise using a simple meter, andTest Method E1503. ANSI 12.18 provides a method of obtaining repeatable sound pressure levelmeasurements of the sound emitted by a source. This docum
5、ent differs in that atmospheric and groundeffects are not controlled. Thus, the results may not repeat if atmospheric conditions or groundconditions between the source and the measurement position change. This guide provides only amethod of accurately documenting the sound levels occurring at the me
6、asurement position at the timeof measurement.1. Scope1.1 This guide covers the measurement of outdoor sounddue to a fixed sound source such as a siren, stationary pump,power plant, or music amphitheater. Procedures characterizethe location, sound level, spectral content, and temporalcharacteristics
7、of that sound source at the time of measurement.Users should be aware that wind and temperature gradients cancause significant variations in sound levels beyond 300 m.With appropriate caution, the use of measurements resultingfrom this guide include but are not limited to:1.1.1 Assessing compliance
8、with applicable regulations,1.1.2 Monitoring the effectiveness of a noise reduction plan,1.1.3 Verifying the effectiveness of measures for mitigationof noise impact,1.1.4 Validating sound prediction models, and1.1.5 Obtaining source data for use in sound predictionmodels.1.2 This standard does not p
9、urport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2
10、C634 Terminology Relating to Building and EnvironmentalAcousticsE1014 Guide for Measurement of Outdoor A-WeightedSound LevelsE1503 Test Method for Conducting Outdoor Sound Mea-surements Using a Digital Statistical Sound AnalysisSystem2.2 ANSI Standards:3S1.4 Specification for Sound Level MetersS1.11
11、 Octave-band and Fractional Octave-band Analog andDigital Filters, Specifications forS1.13 Methods for the Measurement of Sound PressureLevels in AirS1.14 Recommendations For Specifying And Testing TheSusceptibility Of Acoustical Instruments To RadiatedRadiofrequency Electromagnetic Fields, 25 Mhz T
12、o 1 GhzS1.17 Microphone Windscreens - Part 1: Measurements andSpecification of Insertion Loss in Still or Slightly MovingAir1This guide is under the jurisdiction of ASTM Committee E33 on Building andEnvironmentalAcoustics and is the direct responsibility of Subcommittee E33.09 onCommunity Noise.Curr
13、ent edition approved May 1, 2012. Published August 2012. Originallyapproved in 1996. Last previous edition approved in 2004 as E178004. DOI:10.1520/E1780-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of AS
14、TMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Consh
15、ohocken, PA 19428-2959, United States.S12.1 Guidelines for the Preparation of Standard Proce-dures to Determine the Noise Emission from SourcesS1.40 Specification for Verification Procedures for SoundCalibratorsS1.43 Specifications for Integrating-Averaging Sound LevelMetersS12.18 Procedures for Out
16、door Measurement of SoundPressure Level2.3 IEC Standard:4616721 Electroacoustics - Sound Level Meters - Part 1:Specifications3. Terminology3.1 For definitions of terms used in this guide including, butnot limited to, barrier, dummy microphone, equivalent soundlevel, Leq, impulse sound, interference,
17、 measurement plan,measurement set, noise floor, self-noise, and time averagesound level, see Terminology C634.3.2 fixed sourceany permanently installed equipment ca-pable of emitting sound on a regular basis such as a pump,power station, warning siren or sound amplification systempermanently install
18、ed or stationary for a concert.4. Significance and Use4.1 Situations for which outdoor sound level data arerequired include, but are not limited to, comparison of soundlevels with criteria or regulatory limits.4.2 This guide provides information to (1) measure outdoorsound level in the vicinity of o
19、utdoor fixed noise sources, and(2) document other observations necessary for the measure-ments. This guide provides a standard procedure for a trainedacoustical professional that will produce results and documen-tation which are consistent with the purposes cited in 1.1.1-1.1.5.4.3 These sound measu
20、rements should be performed by orunder the direction of a person experienced in the measurementand analysis of outdoor sound, and who is familiar with the useof the required equipment and techniques.4.4 This guide can be used by individuals, regulatoryagencies, or others as a measurement guide to co
21、llect data onthe sound level received from a fixed source within theconstraints cited in Section 8 and Appendix X1 and AppendixX2.4.5 This guide can be used to establish compliance ornoncompliance at the time, distance, and conditions duringwhich the data were obtained. However, this guide is only a
22、measurement procedure and does not address the problem ofprojecting the acquired data outside those conditions, othertimes of day, other distances, or comparison with specificcriteria. In particular, for a given sound source level, distantnoise levels will often be found to be greater at night thand
23、uring the day.5. Apparatus5.1 Acoustical Measurements:5.1.1 Sound Level MeterUse a Type 1 or Type 2 integrat-ing, or averaging sound level meter as defined by ANSI S1.43and IEC 616721 with statistical analysis and capability andwith a dynamic range of at least 60 dB.5.1.1.1 The instrument should hav
24、e a buffered AC signaloutput port to permit the use of headphones. If measurementsare to be made in fractional octave-bands, the system shouldinclude filter sets that fulfill the objectives of the measurementplan. Filters should meet the requirements of ANSI S1.11.5.1.1.2 The instrument shall be equ
25、ipped with anA-Weighting network. It is recommended that the instrumentalso be equipped with a C-weighting network or a Z-weighting,or both.NOTE 1Z-weighing is an unweighted (flat) network, that is sometimescalled “Linear” by manufacturers.5.1.1.3 If “fast” or “slow” response is used, it should be s
26、ostated in the report.5.1.2 Outdoor Microphone SystemAt a minimum theoutdoor microphone system should consist of the following:5.1.2.1 Microphone and preamplifier recommended by themanufacturer of the measurement instrument, and compatiblewith and supporting theANSI Type 1 or Type 2 requirement ofth
27、e sound level meter portion of the system. The microphoneshould also meet the measurement requirements for frequencyresponse, directional response and internal background noise(self-noise).5.1.2.2 The windscreen recommended by the manufacturermay not be adequate in quiet environments with mild windc
28、onditions.5.1.2.3 The microphone system should include the follow-ing features as appropriate for the time duration and weatherconditions expected during the measurement set.5.1.2.4 Microphone and preamplifier system that does notexperience a sensitivity or frequency response change beyondANSI Type
29、1 or Type 2 limits caused by moisture andtemperature effects during the course of the measurement.5.1.2.5 Microphone rain shield for use when applicable.5.1.3 TripodA tripod of the type normally used forsupporting photographic equipment, a mast, or other supportsufficiently strong to support the wei
30、ght of the microphone,possibly the sound level meter and attached protective equip-ment.5.1.3.1 To prevent fouling of windscreens by roosting birdsduring long term and unattended measurement, it is recom-mended that a bird repellant device, known as a “bird spike” beinstalled on the windscreen.5.1.4
31、 Acoustical calibrator (required), with adapters neces-sary to fit the microphone.5.1.5 Headphones (recommended)Headphones for moni-toring the AC output of the sound level meter portion of theanalyzer should have the ability to exclude external sound andprevent sound from the earphones from reaching
32、 the measure-ment microphone. The headphones, with an appropriatebattery-powered driver, should have sufficient frequency re-sponse to permit detection of anomalies in the data caused bywind, humidity, and electrical interference. A frequency re-sponse of 5020 000 Hz is adequate. The headphones or o
33、ther4Available from International Electrotechnical Commission (IEC), 3, rue deVaremb, P.O. Box 131, CH-1211 Geneva 20, Switzerland, http:/www.iec.ch.E1780 122load should be correctly matched to the source impedance ofthe sound level meter AC output port.NOTE 2Caution: Headphone impedance may not be
34、compatible withthe AC output port of some sound level meter instruments. An impedancematching amplifier (buffer) may be required. Failure to use such anamplifier, when needed, can cause the meter to produce inaccurate results.If the sound level meter circuit is modified to use headphones, a function
35、alcheck and calibration of that sound level meter must be performed by aqualified technician before using that instrument.5.1.6 When there is likelihood of rain, extreme heat orhumidity, or of extreme cold conditions, an enclosure capableof protecting the critical components of the measurementinstru
36、ments from causing measurement error should be pro-vided. (See 5.1.4 regarding protection for the microphone.)5.2 Physical Measurements:5.2.1 DistanceTo ensure an accuracy of 1 dB in valuesobtained from calculations that include the results of distancemeasurements, the accuracy of the distance measu
37、rements tobe used in calculations must be within 5 %. A Global Position-ing System (GPS) or any technique that provides this degree ofaccuracy is satisfactory. If the data are to be used for modeling,and if the study area is undulating in nature, and the variationin elevation exceeds2m(6ft), it is r
38、ecommended that atopographical map be consulted for estimating elevation ofsound sources, potential receptors, and potential acousticalbarriers.5.2.2 DirectionA pocket compass should be used for sitelayout work and a wind vane capable of measuring winddirection in octants should be used for determin
39、ation of winddirection.5.2.3 Site MapA scale map of the measurement siteenvirons should be available while preparing for measure-ments.The fixed source position and all measurement locationsshould be annotated on that map.5.3 Meteorological Observations:5.3.1 Observe and record wind speed, relative
40、humidity, andtemperature for potential effects on the sound level meterinstruments, and these factors plus wind direction for potentialeffects on sound propagation from the fixed sound source toeach measurement location. General accuracy meteorologicalinstruments should be available to measure:5.3.1
41、.1 Wind speed (5-km/h increments),5.3.1.2 Wind direction,5.3.1.3 Relative humidity (in 10 % increments), and5.3.1.4 Dry bulb temperature (in 2C increments).NOTE 3NOAA weather reports may be used for wind, temperature,and humidity data when meteorological instruments are not available onsite.5.3.2 Si
42、te absolute atmospheric pressure may be requiredfor the proper use of the microphone calibrator. See AppendixX1.5.4 PhotographsA camera should be carried by the mea-surement team for the purpose of documenting the equipmentsetup and surroundings at least once at each measurementlocation.6. Calibrati
43、on and Self-Noise6.1 The measurement system should be calibrated and itsself-noise, also known as “noise floor” determined according toAppendix X1.7. Interference from Airborne Sound andElectromagnetic Fields7.1 Sound level meter measurements are subject to interfer-ence from a number of sources, so
44、me of which are discussed inAppendix X2. See also ANSI S1.14.8. Measurement Plan and Procedure8.1 A measurement plan should be established to produceaccurate data according to the stated objectives of the test.These objectives should be coordinated with the sponsoringperson or agency, and if possibl
45、e with representatives of anycontending person or agency.8.2 Measurement LocationsEstablish a source envelopewhich just encloses the noise sources. This may be a rectangleA 3 B, or any other appropriate shape around the fixed sourceor source complex, for example, a pumping station or amphi-theatre.
46、Prescribe a measurement surface at 10 m or some otherfixed distance from that inner surface and where there isconfidence that the measurements so made will be meaningfulin representing the sound level in that azimuthal direction ofthat or other identical fixed noise sources in the foreseeablefuture.
47、 See Fig. 1. Sound level measurements should be madeon this source emission surface for reference in evaluatingsound level data obtained at greater distances.8.2.1 Use USGS or other satellite imagery topographicmaps or appropriate site plans as a graph layout medium.Circumscribe circles outside and
48、centered on the centroid ofFIG. 1 Arrangement of Measurement Locations About a FixedSourceE1780 123the source envelope. The radius ranges selected should bedivided into nominal logarithmic increments that result inequal decibel level reductions with a minimum of two radii.For example, the set of 30
49、m, 100 m, 300 m, and 1000 m willproduce level reductions of about 10 dB each over hardground, but any convenient values may be used. Over softground, the decay of the first 30 m could be greater. It isemphasized that at distances beyond 30 m and especiallybeyond 300 m, the sound diminishment with distance will bestrongly influenced by wind, temperature gradients, and groundconditions. In addition, the received level is modified byinterference between the direct wave and the wave reflectedfrom the ground. The maximum radius where measurementswill be significant i
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