ASTM_E_1376_-_90_2002.pdf

Designation:E 1376 90(Reapproved 2002)Standard Test Method forMeasuring the Interzone Attenuation of Sound Reflected byWall Finishes and Furniture Panels1This standard is issued under the fixed designation E 1376;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last 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 is one of a series for the measurement and evaluation of acoustical componentsaffecting speech privacy in open-plan spaces.This test method provides a means of objectivelymeasuring the degree to which sound reflected by furniture panels and wall finishes is attenuated.1.Scope1.1 This laboratory test method2measures the degree towhich reflected sound is attenuated by the most commonlyfound vertical surfaces in open-plan spaces.Reflection ofsound from vertical surfaces is a concern in open-plan spacesbecause it can reduce speech privacy.The vertical surfacescovered by this test method include wall finishes such assound-absorbent panels,and furniture panels or screens.It doesnot cover such items as window finishes or furniture other thanpanels.1.2 This test procedure was originally developed using thefoot-pound system of units for prescribing measurement posi-tions and distances.However,the use of SI units is preferred byASTM.For this reason,dimensions are provided in SI units,with approximate foot-pound conversions indicated in paren-theses.1.2.1 Unless otherwise qualified,all dimensions specified inthis test method shall be understood to have a tolerance of 625mm(61 in.),even though the indicated approximate conver-sion of the numerical dimensions given will not always beaccurate to this extent.All measurements shall be made in SIunits or the corresponding exact foot-pound units.1.3 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 applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:C 423 Test Method for Sound Absorption and Sound Ab-sorption Coefficients by the Reverberation Room Method3C 634 Terminology Relating to Environmental Acoustics3E 795 Practices for Mounting Test Specimens DuringSound Absorption Tests3E 1110 Classification for Determination of ArticulationClass3E 1130 Test Method for Objective Measurement of SpeechPrivacy in Open Offices Using Articulation Index3E 1179 Specification for Sound Sources Used for TestingOpen Office Components and Systems32.2ANSI Standards:S1.4 Specification for Sound Level Meters4S1.6 Preferred Frequencies and Band Numbers for Acous-tical Measurements4S1.11 Specification for Octave Band and Fractional-OctaveBand Analog and Digital Filters4S1.12 Specification for Laboratory Standard Microphones43.Terminology3.1 DefinitionsFor definitions of terms used in this testmethod,see Terminology C 634.The term source point isdefined in Specification E 1179.3.2 Definitions of Terms Specific to This Standard:3.2.1 furniture panela furnishing that does not extend tothe ceiling,and that is used to subdivide an open-plan space1This test method is under the jurisdiction of ASTM Committee E33 onEnvironmentalAcoustics and is the direct responsibility of Subcommittee E33.02 onOpen Plan Spaces.Current edition approved July 27,1990.Published September 1990.2This test method is similar to a procedure developed by the U.S.GovernmentGeneral Services Administration,Public Buildings Service,designated“PBS-C.2,Procedure X,Test Method for the Sufficient Verification of Speech-Privacy PotentialBased on Objective Measurements Including Methods for the Rating of FunctionalInterzone Attenuation and NC-Background,”April 1980.3Annual Book of ASTM Standards,Vol 04.06.4Available from American National Standards Institute,25 W.43rd St.,4thFloor,New York,NY 10036.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.and provide some degree of visual and acoustical privacy.Furniture panels include interlocking systems furniture andfreestanding screens.3.2.2 interzone attenuationat a specified position for aone-third octave-band,the difference between the sound pres-sure level at a nominal reference position 0.9 m(3 ft)from thesound source and the sound pressure level at the point inquestion.3.2.3 nominal interzone attenuationfor a one-thirdoctave-band,at a specified position,the arithmetic meaninterzone attenuation calculated using the interzone attenuationfor the position in question and for two adjacent positions 0.3m(1 ft)to either side.For example,the nominal interzoneattenuation at the 3.0-m(10-ft)position is the arithmetic meanof the interzone attenuations at the 2.7,3.0,and 3.3-m(9,10,and 11-ft)positions.(S