NRC SAA Sound Absorption Coefficient Vs Frequency

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Title: Sound Absorption Test ResultsProduct: 2" Echo Eliminator (3lb. pcf)Application: Wall and CeilingTesting Standard: ASTM C423 A-MountTest Date: 05/18/1999Why this test: This test evaluates a products efficiency of absorbing sound at multiple frequencies.The test simulates the product’s acoustical performance with a direct installation on a wall or ceiling.Test Result Summary: NRC - 1.15; SAA - 0.95NRC1.15SAA0.95Frequenc y(Hz)Abs orptionCoeffic 5001.0131501.0140001.0350001.200.02Sound Absorption Coefficient100Sound Absorption Coefficient vs 6003150One-Third Octave Frequency (Hz)1.02Test ID: AS-SA1448CASI TEST RESULT DISCLAIMERASI makes every effort to ensure the accuracy and reliability of the information provided. Laboratory testing is conducted by independent testing organizations.ASI does not guarantee that field tests or independent tests will not vary. 2018 ASI123 Columbia Court North Suite 201 Chaska, MN 55318TOLL B

ACOUSTIC SYSTEMSACOUSTICAL RESEARCH FACILITYOFFICIAL LABORATORY REPORTAS-SA1448CSubject: Sound Absorption TestDate: 18 May, 1999Contents:Sound Absorption Data, 1/3-octave bandsAbsorption Coefficients, 1/3-octave bandsNoise Reduction CoefficientonEcho Eliminator 3# Density Natural Fiber Acoustic Board – Thickness 2"forRendered by Manufacturer and released to:Acoustical Surfaces123 Columbia Court NorthChaska, MN 55318ACOUSTIC SYSTEMS ACOUSTICAL RESEARCH FACILITY isNVLAP-Accredited for this and other test proceduresNational Institute of Standardsand TechnologyNational VoluntaryLaboratory Accreditation ProgramCertified copies of the Report carry a Raised Seal on every page.Reports may be reproduced freely if in full and without alteration.Results apply only to the unit tested and do not extend to other same or similar items.The NVLAP logo may not be used to claim product endorsement by the U.S. Government415 East Saint Elmo Road Austin, Texas 78745 PO Box 3610 (78764) 512/444-1961 FAX 512/444-2282 800/ e-mail:

AS-SA1448C Page 2 of 4; Revision 0INTRODUCTION“The sound absorption coefficient is a property of the material composing the surface. It is ideally defined as thefraction of the randomly incident sound power absorbed by the surface.” [ASTM C 423]APPLICABLE STANDARDSASTM C 423 - 09a “Standard Test Method for Sound Absorption and Sound Absorption Coefficients by theReverberation Room Method”.ASTM E 795 - 93 “Standard Practices for Mounting Test Specimens during Sound Absorption Tests”.TEST SPECIMENThe test specimen consisted of composition acoustic material whose overall dimensions were: 2438 mm in widthby 2743 mm in length by 50.8 mm in depth [96 x 108 x 2 inch]. The test specimen was manufactured, submitted for test, and designated "3# Density Natural Fiber Acoustic Board - Thickness 2" by manufacturer forAcoustical Surfaces Inc. 123 Columbia Court North, Suite 201, Chaska MN 55318. The manufacturer providedthe test specimen in four (4) equal pieces of the dimension 1219 mm by 2743 mm by 25.4 mm [48 x 108 x 1inch], each having a density of 48.1 kg/m3 [3 pounds per cubic foot]. These individual pieces were arranged soas to arrive at the final overall specimen dimensions. At the request of the manufacturer, additional details of thematerial’s composition are withheld from this report for the purposes of safeguarding proprietary control overthis product. (These construction details remain as part of the controlled test file to fulfill test specimendocumentation requirements.)The weight of the test specimen was 16.6 kg [36.5 pounds]. The test specimen was tested in a Type A Mount instrict accordance with ASTM E 795 requirements.DESCRIPTION OF TESTThe decay rate of sound [which is inversely related to sound absorption] is measured upon terminating a steadystate broadband pink noise signal in the 254 m3 reverberation chamber. Five ensemble averages containingthirty-two decays each are measured with both the test specimen inside of and removed from the chamber. Thedifference between these sound absorptions at a given frequency is defined as the sound absorption of thespecimen. The Sound Absorption Coefficient is the Sound Absorption per unit area of the test specimen. TheNoise Reduction Coefficient (NRC) is a four-frequency average of the Sound Absorption Coefficient. A rotationmicrophone boom and a Norsonic Instruments NI-830 Dual Channel Real Time Analyzer, computer controlledusing custom software, are used for all measurements. Measurements are made in the ISO-Preferred one-thirdoctave bands from 100 Hz to 5000 Hz. The test was conducted in strict accordance with ASTM C 423 - 90aexcept where noted. This test took place at ACOUSTIC SYSTEMS ACOUSTICAL RESEARCH FACILITY,Austin, Texas, on 14 May, 1999.

AS-SA1448C Page 3 of 4; Revision 0SOUND ABSORPTION DATAThe measured Sound Absorption [in units of area] and Sound Absorption Coefficients of the test specimenat the preferred one-third octave band center frequencies are tabulated below and then presented graphicallyBAP 3# Density Natural Fiber Acoustic Board – Thickness 2"AS-SA1448CFrequency Sound Absorption 250031504000500002 1.02.3 0.72.7 0.54.2 0.46.3 0.36.9 0.28.2 0.28.8 0.28.7 0.28.4 0.28.2 0.27.6 0.27.4 0.27.1 0.26.7 0.26.8 0.26.9 0.26.8 0.2Sound Absorption 1.16 0.10 0.08 0.06 0.04 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03Notes[a][a]Noise Reduction Coefficient 1.15[a] denotes empty room absorption was greater than 0.06 as required by ASTM C423. Round robin testing with other laboratories indicate results are neverthelessreliable at 125 Hz. [b] denotes that a significant effect due to changes in test chamber temperature and humidity was noted. Actual results in these bands aretypically not greater than 1.00. [c] due to the very low absorption of the specimen tested, actual absorption values cannot be determined within the reverberation timeuncertainties of the chamber itself. The result for this hand should be considered inconclusive.During the test, environmental conditions in the reverberation chamber were 25.7C and 77.6% relativehumidity. The precision values [ ] tabulated above represent 95% probability that the true mean value lieswithin the stated range.Respectfully Submitted,Michael C. BlackLaboratory Technical Director

AS-SA1448C Page 4 of 4; Revision 0Echo Eliminator B.A.P.3# Density Natural Fiber Acoustic Board–Thickness 2"AS-SA1448C; NRC 1.151.401.32 1.291.22Sound Absorption Coefficient1. 1.01 1.03 1.020.940.800.640.600.400.400.350.200.000.02100 125160200250 315400 500 630800 1000 1250 1600 2000 2500 3150 4000 5000One-third Octave Band Center Frequency (Hz)

Testing Standard: ASTM C423 A-Mount Test Date: 05/18/1999 Why this test: This test evaluates a products efficiency of absorbing sound at multiple frequencies. The test simulates the product’s acoustical performance with a direct installation on a wall or ceiling. Test Result Summary: NRC - 1.15; SAA - 0.95 Test ID: AS-SA1448C NRC SAA 1.15 0.95 Frequency (Hz) Absorption Coefficient 100 0.02 .

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