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ISO 13472-2: 2010 specifies a test method for measuring in situ the sound absorption coefficient of road surfaces with an impedance tube. This method enables evaluation of sound absorption characteristics without damaging the surface.
The SW420R was designed according to ISO 134722, and the performance satisfies the requirement of ISO 13472. The test results can be used to qualify the absorption characteristics of road surfaces for vehicles, tyre testing and other traffic noise studies. However, the field of application is limited to low absorption surfaces, such as those in accordance with ISO 18044. The method is not reliable if the measured sound absorption coefficient exceeds 0.15.
The new BSWA SW420R impedance tube system for pavements absorption testing can be matched with the PA50 power amplifier, MC3522 D/A and VA-Lab IMP software. BSWA highlights the selected sealing material used at the bottom of the tube, reducing the leak of sound signal.
Specifications for the new BSWA SW420R include ISO13472-2:2010, ISO10534-2:1998, and GB/T 18696.2-2002 standard measurements with a frequency range from 250-1600Hz(1/3Octave) / 220-1800Hz.
The tube measurement solution uses a 680mm long tube (including handle) with an inner diameter of 100mm. The SW100-R tube is made with a rounded steel plate of 10mm thickness and 185mm external diameter, featuring two 1/4” ICCP MPA416 microphones with 80mm spacing at 150mm to the ground.
The complete solution weights 14Kg and is delivered in a road case with a calibrator, an optional totally reflective tube, microphones and audio cables.
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Established in 1998, BSWA Technology Co., is a manufacturer of acoustical measurement solutions, headquartered in Beijing. BSWA currently employs 100 staffs with branch offices in Shanghai, Guangzhou, and Chengdu and its products are distributed in over 40 countries. BSWA Products’ cover a full range of acoustic measurement devices, from microphones and sound level meters, measuring systems, material testing, audio testing, outdoor monitoring systems, sound sources and accessories.
www.bswa-tech.com