Some Pitfalls in Using AS2377:2002 for Passby Noise Measurement

The measurement of passby noise for type testing of rail vehicles in Australia is governed by AS2377:2002 Measu rement of Noise from Railbound Vehicles. This standard is referenced by many organisations including RailCorp, ARTC and Queensland Rail, and therefore type tests for rail vehicles on most Australian rail networks are conducted in accordance with its recommendations. AS2377:2002 lags behind the latest European standards such as ISO3095:2005 Measurement of Noise Emitted by Railbound Vehicles in two important areas however; it provides no guidance regarding either the acoustic scale roughness of the rails or the track decay rate of the test track section. This paper explores the implications of these issues, provides examples of the resulting changes in noise that can result, with consequences for compliance with RailCorp’s EPA licence, and describes how these important track properties are handled in ISO3095:2005.