This document describes a test method for determining the intrinsic characteristics of sound diffraction of added devices installed on the top of railway noise barriers. The test method prescribes measurements of the sound pressure level at several reference points near to the top edge of a noise barrier with and without the added device installed on its top. The effectiveness of the added device is calculated at the difference between the measured values with and without the added devices, correcting for any change in height (the method described gives the acoustic benefit over a simple barrier of the same height; however, in practice the added device can raise the height and this would provide additional screening depending in the source and receiver positions.
Registration number (WIID)
39094
Scope
This document describes a test method for determining the intrinsic characteristics of sound diffraction of added devices installed on the top of railway noise barriers. The test method prescribes measurements of the sound pressure level at several reference points near to the top edge of a noise barrier with and without the added device installed on its top. The effectiveness of the added device is calculated at the difference between the measured values with and without the added devices, correcting for any change in height (the method described gives the acoustic benefit over a simple barrier of the same height; however, in practice the added device can raise the height and this would provide additional screening depending in the source and receiver positions.
