Product Testing

Research demonstrates that vehicles traveling on a highway or interstate generate noise at a range of frequencies from 50 to 4,000 Hz with most of the noise levels concentrated at 50 to 800 Hz.

With that data in hand, Paragon Noise Barriers conducted tests of Noise D-Fence™ using a modified ASTM E90 testing configuration. The sounds generated for the testing phase were created from a CD of fixed sounds across the frequencies of 63 Hz to 8,000 Hz. The Noise D-Fence™ configuration included 2 panels stacked one on top of another (total height, 8 feet and total length, 12 feet). All measurements were made outdoors (rather than the standard E90 test which is conducted indoors) to test the panels in their actual site configuration. Compared to a standard indoor ASTM E90 test, these open air sound tests are conservative. In the E90 test there are walls and a ceiling to prevent sound from going over and around the test specimen. Paragon Noise Barriers' tested configuration provides results that are more conservative than would be typical of an actual highway sound wall construction.

The following table illustrates the reduction in decibels Noise D-Fence™ provides. The average sound level reduction measured at 4 feet behind the wall was 27dB. At 50 feet behind the wall, the average sound reduction was 34 dB.