FOR: Ready Acoustics LLC Sound Absorption Test. ON: RT424 4 Inch Thick Ready Traps Page 1 of 3

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1 FOR: Ready Acoustics LLC Sound Absorption Test Elk River, MN RAL -A ON: RT424 4 Inch Thick Ready Traps Page 1 of 3 CONDUCTED: 25 May 2006 TEST METHOD The test method conformed explicitly with the requirements of the ASTM Standard Test Method for Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method: ASTM C423-02a and E Riverbank Acoustical Laboratories has been accredited by the U.S. Department of Commerce, National Institute of Standards and Technology (NIST) under the National Voluntary Laboratory Accreditation Program (NVLAP) for this test procedure (NVLAP Lab Code: ). A description of the measuring procedure and room qualifications is available separately. DESCRIPTION OF THE SPECIMEN The test specimen was designated by the manufacturer as RT424 4 inch thick Ready Traps. The specimen consisted of eight (8) units. Each unit as measured was nominally 610 mm (24 in.) wide by 1.22 m (48 in.) long and 102 mm (4 in.) thick. The specimen was tested in the laboratory's 292 m 3 (10,311 ft 3 ) test chamber. The manufacturer's description of the specimen was as follows: Each unit consisted of 2 pieces of 2 inch thick Owens Corning insulation 703, 3 PCF wrapped in polyester acoustical stretched suede. A visual inspection verified the manufacturer's description of the specimen. The weight of the entire specimen as measured was 29 kg (64.25 lbs), an average of 3.6 kg (8 lbs) per panel. The room temperature at the time of the test was 22ºC (71ºF) and 64±2% relative humidity. MOUNTING J Seven panels were distributed about the test chamber as follows: Three units each on the south and north walls and one unit on the west wall. Respective to each wall surface the panels were located at a 45º angle supported at both the wall and floor with the long dimension of the panel parallel to the wall-floor intersection. The panels were located nominally 203 mm (8 in.) apart. An eighth panel was located at a nominal 45º angle in the southwest corner of the room. The panel was suspended vertically with bottom edge hanging 622 mm (24.5 in.) from the test room floor. The sides of the face of the panel were butted against the south and west wall surfaces.

2 Ready Acoustics LLC RAL -A May 2006 Page 2 of 3 TEST RESULTS 1/3 Octave Center Frequency (Hz) Absorption Sabins/Unit Total Absorption In Sabins ** ** ** ** ** ** Tested by Approved by Marc Sciaky David L. Moyer Senior Technician Laboratory Manager

3 SOUND ABSORPTION REPORT RAL-A Page 3 of 3

4 1512 S. Batavia Avenue Geneva, Illinois Ph: Fax Founded in 1918 by Wallace Clement Sabine Appendix to Sound Absorption Test: RAL -A Attachment No. of Pages Specimen Mounting Details 1 Specimen Mounting Room Layout 1 Extended Frequencies 1 Measurement Uncertainty 1

5 Mounting Detail TEST NUMBER: TEST DATE: CLIENT: DESIGNATION: DIMENSIONS: NUMBER OF UNITS: RAL -A MAY 25, 2006 Ready Acoustics LLC RT424 4 Inch Thick Ready Traps 24" x 48" x 4" 8 3 specimens each on the south and north wall with nominal 8 spacing between specimens. 1 specimen on west wall. 1 specimen in the southwest corner vertically oriented with bottom edge a nominal 24.5 above test room floor [nominal 18 above 6.5 floor ledge]. All specimens 45 degree angle to wall with the backside long axis edges resting against the test room wall / floor. See figures 1 & 2 below. Figure 1 Figure 2 ADDITIONAL INFORMATION IS PROVIDED ON THE ATTACHED FLOOR DIAGRAM PAGE RALA Appendix Page 1 of 4

6 RALA Appendix Page 2 of 4

7 FOR: Ready Acoustics LLC An Appendix To Elk River, MN RAL-A ON: RT424 4 Inch Thick Ready Traps CONDUCTED: 25 May 2006 SUBJECT: Additional Frequency Data for Absorption Testing As requested by the client, sound absorption values were calculated at additional test frequencies. Although the measurements were made in accordance with the procedures described in ASTM C423-02a, they do not qualify as part of the standard. Since the results are representative of the test environment only, they are unofficial and intended for research and development guidelines rather than for commercial purposes. The sound absorption values at additional frequencies were as follows: RAL-A /3 Octave Center Absorption Total Absorption (Hz) Sabins/Unit Sabins RALA Appendix Page 3 of 4

8 FOR: Ready Acoustics LLC An Appendix To Elk River, MN RAL-A ON: RT424 4 Inch Thick Ready Traps CONDUCTED: 25 May 2006 SUBJECT: Additional Measurement Uncertainty Data As requested by the client, the uncertainties of the measured sound absorption values were calculated and are presented below. The absorption of the test specimen contains the combined uncertainties of the two room absorptions: the absorption of the empty room and the absorption of the room containing the test specimen. For the total number of 80 decays conducted for both the empty room and the room containing the test specimen, the standard deviation of the decay time was determined and used with the appropriate t-distribution factor and the mean to derive the 95% confidence limits. The uncertainties were combined using the usual "root-sum-of-squares" method. Room uncertainties are used internally for quality control purposes although these uncertainties are not established as criteria for conducting the test. More information regarding room qualifications, reproducibility, R, and repeatability, r, can be found in the current ASTM C423 standard. 1/3 Octave Center Frequency Absorption Per Unit Total Absorption (Hz) (Sabins) (Sabins) % Uncertainty With 95% Confidence RALA Appendix Page 4 of 4