ASTM E1130-2008 Standard Test Method for Objective Measurement of Speech Privacy in Open Plan Spaces Using Articulation Index《使用声音清晰度指数在开放式空间对谈话保密性进行客观量度的标准试验方法》.pdf

1、Designation: E 1130 08Standard Test Method forObjective Measurement of Speech Privacy in Open PlanSpaces Using Articulation Index1This standard is issued under the fixed designation E 1130; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev

2、ision, the year of last revision. 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 test methods for evaluating speech privacy in buildings. It is designed

3、tomeasure the degree of speech privacy between locations in open plan spaces, where occupants areseparated only by partial-height partitions and furnishings. Another proposed test method deals withassessing speech privacy for closed rooms. A related test method deals with the laboratorymeasurement o

4、f interzone attenuation open plan components intended to provide speech privacy, suchas partial height space dividers, ceiling systems and wall finishes.1. Scope1.1 This test method describes a means of measuring speechprivacy objectively between locations in open plan spaces.This test method relies

5、 upon acoustical measurements, pub-lished information on speech levels, and standard methods forassessing speech communication. This test method does notmeasure the performance of individual open plan componentswhich affect speech privacy; it measures the privacy whichresults from a particular confi

6、guration of components (1, 2).21.2 This test method is intended to be a field test for themeasurement of speech privacy in actual open plan spaces.However, this test method could be used in an environmentarranged to simulate an open plan space.1.3 This test method is suitable for use in many open pl

7、anspaces such as open plan offices, healthcare spaces, institu-tional spaces, schools, etc. It is not applicable for measuringthe speech privacy between open plan and enclosed spaces orbetween fully enclosed spaces.1.4 This test method relies upon the Articulation Index,which objectively predicts th

8、e intelligibility of speech. Whileboth the Articulation Index and this test method can beexpected to reliably predict average speech privacy, neitherpredicts the specific degree of speech privacy afforded toparticular open plan occupants.1.5 The values stated in SI units are to be regarded as thesta

9、ndard. The inch-pound units in parentheses are for informa-tion only.1.6 This standard does not purport 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

10、applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3C 634 Terminology Relating to Building and Environmen-tal AcousticsE 1179 Specification for Sound Sources Used for TestingOpen Office Components and Systems2.2 ANSI Standards:4S1.4 Specification for Soun

11、d Level MetersS1.6 Preferred Frequencies, Frequency Levels, and BandNumbers for Acoustical MeasurementsS1.11 Specification for Octave-Band, and Fractional-Octave-band Analog and Digital Filters3. Terminology3.1 DefinitionsThe acoustical terminology used in thistest method is consistent with Terminol

12、ogy C 634. Of specialimportance are the terms average sound pressure level andarithmetic mean sound pressure level, both of which aredefined in Terminology C 634, and source point which isdefined in Specification E 1179.1This test method is under the jurisdiction ofASTM Committee E33 on Buildingand

13、Environmental Acoustics and is the direct responsibility of SubcommitteeE33.02 on Open Plan Spaces.Current edition approved Sept. 1, 2008. Published September 2008. Originallyapproved in 1986. Last previous edition approved in 2002 as E 1130 021.2The boldface numbers in parentheses refer to the list

14、 of references at the end ofthis test method.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Available from

15、American National Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.Available 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 Conshohocken, PA

16、19428-2959, United States.4. Summary of Test Method4.1 Select two locations in an open plan environment,between which the speech privacy is to be measured. Designateone location as the talker or source location and the other as thelistener or measurement location. These locations should typifythe us

17、ual positions of occupants.4.2 All masking sound systems and HVAC systems shall beoperating in their usual manner.4.3 At the listener location, measure the ambient soundpressure levels in each one-third octave-band from 200 to 5000Hz and the A-weighted sound level.4.4 Locate a qualified sound source

18、 at the talker locationand orient it toward the listener location. Drive the source withpink or white noise at a level sufficient to increase the one-thirdoctave-band sound pressure levels at the measurement locationby at least 10 dB above the ambient over the entire frequencyrange of interest. The

19、sound pressure levels produced by thesound source at a 1.0 m (3.3 ft) reference position in ananechoic room for a known electrical input will have beenpreviously established (3).4.5 Measure the sound pressure levels in one-third octavebands at the listener location with the source on.4.6 Calculate t

20、he level reduction in each one-third octaveband, that is, the difference in sound pressure levels producedby the sound source at the 1.0 m (3.3 ft) reference position andat the listener location.4.7 Determine the speech spectra to be used. The normalvoice spectrum of male speech peaks from Table 1 (

21、see also (4)and (7) must be used; optionally, additional spectra may beused.4.8 Calculate the one-third octave-band sound pressurelevels for the speech spectrum at the listener location. This iscarried out by subtracting the measured level reductions fromthe speech spectrum.4.9 Calculate the signal-

22、to-noise ratio in each one-thirdoctave band by subtracting the measured ambient and soundpressure levels from the calculated speech levels at the listenerlocation.4.10 Calculate the Articulation Index in accordance withSection 11 using the one-third octave-band signal-to-noiseratios.4.11 Report the

23、Articulation Index to two decimal places asthe measure of speech privacy.5. Significance and Use5.1 The speech privacy between locations in an open planspace is determined by the degree to which intruding speechsounds exceed the ambient sound pressure levels at thelisteners ear; a classic signal-to-

24、noise ratio situation.5.2 The sound pressure levels at the listeners ear fromintruding speech depend upon:5.2.1 The individual vocal effort and orientation of thetalker,5.2.2 The attenuation of speech signals due to distance orintervening barriers, and5.2.3 The reinforcement of speech signals due to

25、 reflectionsfrom surfaces such as the ceiling, furniture panels, lightfixtures, walls, or windows.5.3 The ambient sound pressure levels will often be con-trolled to mask intruding speech. This is accomplished bymeans of a masking sound system. However, in certainpositions and frequency ranges, heati

26、ng, ventilating, or airconditioning equipment (HVAC) may contribute significantlyto ambient sound pressure levels.5.4 The primary purpose of this test method is to measurethe speech privacy for an average speech spectrum using thestandard Articulation Index method. This requires measure-ment of the

27、relevant acoustical characteristics discussed in 5.2and 5.3 for a pair of locations and calculation of the Articula-tion Index using an average speech spectrum. The averagespeech spectrum is for male talkers speaking with normal voiceeffort.5.5 The Articulation Index ranges from 0.00, where speechis

28、 unintelligible, to 1.00, where all individual spoken words canbe understood. Caution should be exercised in interpreting thenumerical results of this test method. There is a need for furtherresearch to establish the relationship of Articulation Index tospeech privacy. One purpose of this test metho

29、d is to encouragethe measurement of data and further research on this topicperhaps leading to development of well-documented speechprivacy categories and criteria.5.6 This test method can be used to:5.6.1 Compare the relative privacy afforded between differ-ent locations within open plan spaces.5.6.

30、2 Evaluate how changes in open plan components (bar-riers, furniture, ceilings, masking sound, or wall panels) affectspeech privacy.5.6.3 Measure speech privacy objectively for correlationwith subjective responses.5.7 This test method could be one element of a performanceor acceptance test procedure

31、. However, many additional itemswould need to be specified to use this test method forperformance testing of an open plan environment, such as, theTABLE 1 Speech Peaks for MalesA,BOne-ThirdOctave-BandCenterFrequency,HzOne-ThirdOctave-BandSound PressureLevels ofSpeech Peaksfor NormalVoice Effort(dB r

32、e: 20 Pa)One-ThirdOctave-BandSound PressureLevels ofSpeech Peaksfor RaisedVoice Effort(dB re: 20 Pa)200 60 63250 64 68315 63 67400 65 70500 66 72630 64 70800 58 661000 58 651250 59 671600 56 632000 52 592500 53 603150 53 584000 50 565000 46 52ASpeech peaks calculated from rms values given in (4) by

33、adding 12 dB, inaccordance with (7).BTheA-weighted sound level and linear sound pressure level of the normal voiceeffort spectrum given in Table 1 are 70 dB and 73 dB, respectively. Thecorresponding levels for the raised voice effort spectrum are 76 dB and 78 dB.E1130082number of locations to be tes

34、ted and method of selecting thoselocations, and the method of averaging the results. Specifyinga numerical criterion in terms of the Articulation Index is alsonecessary for acceptance testing; however, the selection ofsuch a criterion and permissible deviations should be under-taken with care in vie

35、w of the present state-of-the-art asdiscussed in 5.5.6. Test Space6.1 The test space shall be an actual or a mock-up open planenvironment.6.2 The ceiling of the test space shall be complete, includingceiling board, light fixtures, and air diffusers.6.3 The floor covering and wall finishes shall be c

36、ompletelyinstalled prior to testing.6.4 All furnishings shall be in place.6.5 Any masking sound system shall be set as intended foruse in the occupied space.NOTE 1If the masking system is adjusted to produce significantlyhigher sound pressure levels, greater speech privacy is obtained; however,the h

37、igher levels may be found unacceptably annoying.6.6 The open plan space should be unoccupied during thetests.NOTE 2If the purpose of testing is to evaluate the change in speechprivacy which results from component changes (for example, installingwall finishes or adjusting the masking system) the diff

38、erent conditions foreach test result shall be carefully documented.7. Apparatus7.1 The minimum instrumentation required for this testmethod is as follows:7.1.1 Microphone and Amplifier, that meet or exceed therequirements of ANSI S1.4 for Type 1 sound level meters. Arandom incidence microphone shall

39、 be used, that is, one thathas its flattest frequency response for sounds arriving atrandom angles.7.1.2 One-Third Octave-Band Filter Set, meeting the re-quirements of ANSI S1.11 for class 1 or better. The nominalcenter frequencies of the filters shall include all the preferredone-third octave bands

40、 from 200 to 5000 Hz conforming toANSI S1.6. This range may be extended.7.1.3 Sound Level Meter, or other device from which thesound pressure level can be read.7.1.4 Calibrated Sound Source, of known sensitivity anddirectivity, completely described in Specification E 1179 andcalibrated in accordance

41、 with the Annex of this test method.7.2 On-Site Data Acquisition Instruments, that may consistof a microphone with calibrator, a precision sound level metercapable of measuring average sound pressure level, a one-thirdoctave-band analyzer, and a strip chart recorder (optional). Testdata may be read

42、on-site or recorded for later analysis.Recording instruments may consist of a microphone withcalibrator, precision sound level meter (optional), and aninstrument quality recorder. Laboratory data reduction instru-ments may consist of a recorder, a one-third octave-bandanalyzer and a computer.7.3 The

43、 background noise of measuring instruments in eachone-third octave band must be at least 10 dB below measuredsound pressure levels.8. Test Signal8.1 The test signal shall be contiguous, one-third octavebands of pink or white noise, from 200 to 5000 Hz, and may beextended.9. Speech Spectra9.1 The nor

44、mal voice effort spectrum (2) of speech peaksgiven in Table 1 shall be used for the calculations.Additionally,other spectra may be used such as the raised voice spectrum ofspeech peaks in Table 1.10. Procedure10.1 Measurement Location:10.1.1 Select a listener (measurement) location at the typi-cal e

45、ar-height of a seated or standing listener, that is, themicrophone shall be located 1.2 m (4 ft) above the floor(seated) or 1.67 m (5 ft 6 in.) above the floor (standing).10.1.2 The measurement location should be at least 1 m (3.3ft) from any vertical surfaces such as walls, columns, desks, orfurnit

46、ure. In the event that this cannot be met, the selectedlocation shall be at an occupants usual position.10.2 Ambient Measurements:10.2.1 With the test signal off, the average sound pressurelevel shall be measured in each one-third octave band over atime period of at least4satfour positions at 90 int

47、ervalsaround a circle of 0.3-m (1-ft) radius centered on the listener(measurement) location. The arithmetic mean sound pressurelevel shall be calculated for each band from the four measuredvalues. TheA-weighted sound level shall also be measured andcalculated in this manner. All data shall be obtain

48、ed with themicrophone diaphragm parallel to the floor and facing up-wards.10.2.2 Verify that the measured ambient sound pressurelevels exceed the background noise of the instruments by atleast 10 dB in each band. If not, the data shall not be used.10.3 Source Location and Orientation:10.3.1 The soun

49、d source shall be placed at the talkerlocation and the source point shall be located 1.2 m (4 ft) or1.67 m (5ft 6 in.) above the floor, to represent a seated orstanding talker, respectively.10.3.2 The loudspeaker axis should be oriented so that itsprojection in the horizontal plane is along a straight line fromthe talker to the listener location.10.3.3 In the vertical plane, the loudspeaker axis should beoriented to be 25 above horizontal for a source height of 1.2m (4 ft) or oriented to be horizontal (parallel to the floor) for asource height of 1.67 m (5 ft 6 in.).10.4