1、Designation: E 1111 07Standard Test Method forMeasuring the Interzone Attenuation of Open OfficeComponents1This standard is issued under the fixed designation E 1111; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、 revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONThis test method describes the measurement and evaluation of acoustical performance ofcomponents affecting speech privacy
3、 in open-plan spaces. The maximum privacy theoreticallyavailable at normal working distances in open-plan spaces, with partial height space dividers (screens),is insufficient without the assistance of relatively elevated background masking sound levels. Thus, theprovision of adequate speech privacy
4、in open-plan offices and schools is one of the most difficult tasksin the architectural acoustics field. This test method provides a means of objectively measuring therelevant acoustical characteristics of three major components of open-plan spaces, the ceiling system,furniture panels used as acoust
5、ical barriers, and wall finishes which attenuate reflected sound.Furniture panels may be tested for their capacity as an acoustical barrier and/or the degree to whichthey may reduce reflected sound.1. Scope1.1 This test method covers the measurement of the inter-zone attenuation for three components
6、 of open-plan spaces:1.1.1 Ceiling systems when used in conjunction withpartial-height space dividers. This arrangement is commonlyused in offices to achieve speech privacy between work zonesin the absence of full-height partitions. This test method isapplicable to any ceiling configuration, includi
7、ng, for example,a pattern of sound-reflective panels in an otherwise sound-absorptive ceiling. This test method generally requires use of afixed space divider height of 1.50 m (60 in). In recognition oftrends toward alternate divider heights in open office environ-ments, measurements with an alterna
8、te divider height may beconducted in accordance with this standard.1.1.2 Furniture panels used as acoustical barriers in open-plan spaces to provide speech privacy or sound isolationbetween working positions.1.1.3 Vertical panels, including wall finishes such as sound-absorbent panels, and furniture
9、 panels or screens which mayreflect sound. It may not be applicable to such items as windowfinishes or furniture other than panels if these differ signifi-cantly from flat wall panels.1.1.4 The combination of results from the various compo-nents of an open-plan office is beyond the scope of thisstan
10、dard.1.2 Unless otherwise qualified, all dimensions specified inthis test method shall be understood to have a tolerance of 66mm (614 in.) The values stated in SI units are to be regardedas the standard. The values given in parentheses are providedfor information only.1.3 This standard does not purp
11、ort 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:2C 4
12、23 Test Method for Sound Absorption and Sound Ab-sorption Coefficients by the Reverberation Room MethodC 634 Terminology Relating to Environmental AcousticsE 795 Practices for Mounting Test Specimens DuringSound Absorption TestsE 1110 Classification for Determination of ArticulationClass1This test m
13、ethod is under the jurisdiction ofASTM Committee E33 on Buildingand Environmental Acoustics and is the direct responsibility of SubcommitteeE33.02 on Open Plan Spaces.Current edition approved April 1, 2007. Published April 2007. Originallyapproved in 1986. Last previous edition approved in 2005 as E
14、 1111 05.2For 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.1Copyright ASTM International, 100 Barr Harbor Drive
15、, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 1179 Specification for Sound Sources Used for TestingOpen Office Components and SystemsE 1374 Guide for Open Office Acoustics and ApplicableASTM Standards2.2 ANSI Standards:S1.4 Specification for Sound Level Meters3S1.6 Preferred Frequ
16、encies and Band Numbers for Acous-tical Measurements3S1.11 Specification for Octave Band and Fractional-Octave-Band Analog and Digital Filters33. Terminology3.1 The following terms used in this test method havespecific meanings that are defined in Terminology C 634:3.1.1 acoustical barrier, ambient
17、noise, diffraction, level,(sound) absorption coefficient, sound pressure levels, pinknoise, white noise.3.2 Definitions of Terms Defined in Other Standards notincluded in Terminology C 634:3.2.1 The term source point is defined in SpecificationE 1179.3.3 Definitions of Terms Specific to This Standar
18、d:3.3.1 furniture panela furnishing that does not extend tothe ceiling, and that is used to subdivide an open-plan spaceand provide a degree of visual and acoustical privacy. Furniturepanels include interlocking systems furniture and freestandingscreens.3.3.2 nominal reference levelfor a one-third o
19、ctave-band,the arithmetic mean of sound pressure levels measured atspecified positions relative to the source in a region free fromreflections.3.3.3 interzone attenuationat a specified position, for aone-third octave band, the difference between the nominalreference level and the sound pressure leve
20、l at the specifiedpoint.3.3.4 nominal interzone attenuationfor a one-thirdoctave-band, at a specified point, the arithmetic mean interzoneattenuation calculated using the interzone attenuation for thepoint in question and for two adjacent positions 0.30 m (1 ft)along the survey path.4. Summary of Te
21、st Method4.1 The test facility is essentially an expanse of floor andceiling in which all surfaces excluding the floor and testspecimen have negligible sound reflections. The facility maybe set up in a laboratory, in a mock-up of a proposed building,or in a completed building. The configuration of t
22、he room willdepend on the open-plan component being tested.4.1.1 For testing a ceiling system, a standard space divideris positioned with such dimensions and construction that soundgenerated on one side can reach a measuring point on the otherside only by way of diffraction over the top of the space
23、 dividerand by reflection from the ceiling. With the diffracted compo-nent fixed by the dimensions of the space divider and by theheight of the source and measurement position, the differencebetween the sound pressure levels measured on each side of thespace divider provides a comparative measure of
24、 the contribu-tion of ceiling system reflection to the total sound transmission.See Fig. 1.4.1.2 For a furniture panel tested as an acoustical barrier, thepanel is arranged such that it blocks the direct path of soundfrom the sound source to the measuring microphones. Soundgenerated by the sound sou
25、rce on one side of the furniturepanel under test reaches the other side chiefly by diffractingover its top edge. A potential secondary path is transmission3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.FIG. 1 Ceiling Tes
26、t Configuration, Elevation(speaker is horizontal for other tests)E1111072through the panel. The differences in sound pressure levelsmeasured on each side of the furniture panel provide a measureof its effectiveness as an acoustical barrier. See Figs. 2 and 3.4.1.3 For wall finishes and furniture pan
27、els tested for theircapacity in suppressing reflected sound, the sound is generatedon one side of a standard barrier that extends from floor toceiling, with a gap at the end facing the test specimen, and ispartially reflected by the test specimen to reach the other side.The difference in magnitude o
28、f the sound pressure levelsmeasured on the source and receiving side of the barrierprovides a measure of the attenuation of reflected soundattributable to the properties of the test specimen. Sound-absorbent specimens will reflect less energy around the barrierthan sound-reflective specimens. Two te
29、st conditions are es-tablished in this test method. Specimens that are wall finishesare applied over a sound-reflective side wall, whereas speci-mens that are furniture panels are placed against a sound-absorptive side wall. See Fig. 4.4.2 When the test is conducted in a mock-up of a proposedbuildin
30、g or in a completed building, strict adherence to the testmethod may not be possible in that the conditions of ceilingheight and plenum depth, etc., cannot be met because of thebuilding design. Under these circumstances, the measurementsapply only to that situation and other identical situations.5.
31、Significance and Use5.1 Providing speech privacy in open-plan spaces dependsupon many factors, the most significant of which are thefollowing: (1) the shadow zone of part-height space dividersand the diffraction of sound from the edges of space dividers;(2) the primary sound reflective properties of
32、 the ceilingsystem; (3) the level of masking sound present in the space;and (4) the distance between speaker and listener. GuideE 1374 provides additional detail on the factors contributing tospeech privacy in open-plan spaces.5.2 In this test method the third factor, masking sound, iseliminated and
33、 the fourth factor, the distance between speakerand listener, is standardized for all specimen types. For themeasurement of ceiling systems, the first factor, the shadowzone, is also standardized for each divider height used.Experience has indicated that results obtained by this testmethod may not f
34、airly represent the speech privacy that may beachievable with non-flat ceiling systems. For the measurementof furniture panels used as acoustical barriers, the second ofthese factors, the sound reflectance of the ceiling, is standard-ized. For the measurement of reflective and absorptive verticalsur
35、faces used as wall finishings or furniture panels, the first andsecond factors are standardized and all paths between thespeaker and listener reflecting only off of the ceiling areeliminated.5.3 This test method provides standardized techniques toassess the contribution of specific components of an
36、open-planspace. The test method specifies an acoustical testing environ-ment for each component type that isolates its contributionfrom the contribution of other components, which may inactual open-plan environments contribute significantly to theoverall speech privacy.5.4 The significance of test r
37、esults obtained by this testmethod must also be considered with regard to the attainablemeasurement accuracy. The attainment of speech privacy in thepresence of masking sound is critically dependent upon soundlevel of the speech relative to the masking sound; a change assmall as 2 dB in either the s
38、peech or masking sound maychange the privacy from significant to insignificant. Thenormally accepted test accuracies for sound attenuation mea-surements may be inadequate to evaluate components havingmarginal interzone attenuation performance for open-officeneeds.FIG. 2 Test Configuration for Furnit
39、ure Panels as Acoustical Barriers with Standard Survey Positions, (Plan View)E11110736. Laboratory Test Facility6.1 The plan view dimensions of the facility shall be at least4.57 by 9.14 m (15 by 30 ft). The height of the facility,measured from the floor to the inner face of the sound-absorptive cov
40、ering on the ceiling, shall be at least 2.74 m (9ft). Where ceiling systems are to be measured, additionalheight is required to provide the plenum space described in9.1.1.6.2 The floor shall be of a solid material such as concrete orplywood weighing at least 20 kg/m2(4 lb/ft2). It shall becovered wi
41、th carpet without an underlayment. This is typical ofopen plan spaces. The absorption coefficients of the carpet shallbe measured in accordance with Test Method C 423, and thesound absorption average (SAA) shall lie in the range from0.15 to 0.4.6.3 The walls shall have random incidence sound absorpt
42、ioncoefficients of at least 0.9 for all test frequencies. The wallcovering sound absorption shall be measured in accordancewith Test Method C 423 with a mounting equivalent to thatused in the test facility except where the requirements of 9.3are to be met. To meet the requirements of 9.3, the sounda
43、bsorbing material on sections of a wall may either bedemountable or be covered with a hard surface.6.4 Test configuration shall be as follows:FIG. 3 Test Configuration for Furniture Panels as Acoustical Barriers with Near Survey Positions, (Plan View)FIG. 4 Test Configuration for Furniture Panels as
44、 Acoustically Reflecting Surfaces, (Plan View)E11110746.4.1 For measurements of a ceiling system, a space dividershall extend the full width of the facility between the side wallsand shall be placed at least 2.74 m (108 in.) from both endwalls. The divider shall have a core of rigid, impermeablemate
45、rial weighing not less than 7.0 kg/m2(1.4 lb/ft2), and shallbe faced on both sides with a 51 mm (2.0 in.) thickness ofsound absorbing material. The core shall extend fully to the topof the space divider, as shall the sound absorption facingmaterial. The space divider shall have a minimum SAA of 0.80
46、when measured in general accordance with the provisions fortesting office space dividers in Test Method C 423. There shallbe no gap between the bottom of the space divider and thefloor. If the space divider is assembled in sections, care shall betaken to minimize sound transmission at the joints. Me
47、asure-ments shall be made with a space divider 1.52 m (60 in.) high.Measurements may also be made with a space divider 1.83 m(72 in.) high. See Fig. 1.NOTE 1Since the core and absorptive facings of the divider extend toits top, the divider may not be capped.6.4.2 For measurements on furniture panels
48、 tested as acous-tical barriers: The ceiling covering shall have random inci-dence sound absorption coefficients of at least 0.95 at allfrequencies at which measurements are to be made. See Figs.2 and 3.NOTE 2Since reflections from those portions of the walls and ceilingof the facility which are not
49、 part of the specimen may reduce the measuredattenuations, it is important to eliminate these reflections as much aspossible.6.4.3 For measurements of wall finishes or furniture panelstested for the ability to attenuate reflected sound:6.4.3.1 The ceiling coverings shall have random incidencesound absorption coefficients of at least 0.95 at all frequenciesat which measurements are to be made.6.4.3.2 A standard barrier shall extend from the floor to theceiling of the test facility and shall be no greater than 203 mm(8 in.) thick. It shall comprise a septum of rigid, impermeab