The noise exposure from rail freight is still a major environmental challenge. Main problems are caused by old freight wagons, which still account for the vast majority of the rolling stock. Equipped with iron cast brakes their noise emissions are way above the limits set for new freight cars by the international Technical Standards of Interoperability (TSO). Even for new freight cars available on the market it must be constituted that, although they comply with TSO now noise standards through quieter brake systems, usually are based on decades-old technology of the Y25 bogie.

To utilise the potential of rail it is of great environmental political interest to retrofit existing vehicles with low noise brake systems and to develop innovative technologies that represent a quieter alternative to conventional Y25 bogie. However, the current legal, regulatory, technical, operational and economic frameworks are not or only poorly suited to achieve these goals. Current research suggests that innovative noise reduction measures for new vehicles and low noise technologies for retrofitting existing vehicles beyond the sole replacement of the brake system are already available, or close to market readiness. However, under current market and regulatory conditions a quick up-take by the rail freight sector appears doubtful.