BS EN 1793-1:2012 Road traffic noise reducing devices. Test method for determining the acoustic performance. Intrinsic characteristics of sound absorption
2017BS EN 1793-1:2017 Road traffic noise reducing devices. Test method for determining the acoustic performance. Intrinsic characteristics of sound absorption under diffuse sound field conditions
2013BS EN 1793-1:2012 Road traffic noise reducing devices. Test method for determining the acoustic performance. Intrinsic characteristics of sound absorption