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.
The prevailing research project aims at identifying the barriers to market entry, operation and maintenance procedures of new low noise technologies for freight trains. Based in these findings it looks at current barriers and required changes to the legal and regulatory environment in which the railway industry and the rail transport companies are acting. Across all relevant areas of measures by policy and the industry sectors it will seek for solutions to address current challenges, assessed their feasibility and finally address pathways for action to all relevant actors.
A major instrument of German noise policy towards rail freight is the substitution of cast-iron brake blocks by composite brake blocks. This is expected to be finished by 2020. But even then, rail freight noise will remain on the political agenda. Accordingly, this study concentrates on additional technical measures to further reduce rail freight noise and policies to promote their adoption: solutions for infrastructure, locomotives and - in the focus of this study - freight waggons. The study indicates that, when cast-iron brake blocks have been removed (political goal A), a number of technical measures - often with a smaller reduction potential but also with lower costs - should be used to retrofit the existing freight fleet (goal B). New wagons should be equipped with disc brakes and new wheel profile de-signs (goal C). To encourage the adoption of the multiple technical measures, the study recommends continuing the use of noise-differentiated track access charges and to base differentiations on emission classes. While the access charges system should primarily not entail public subsidies, financial support could be implemented in form of bonus payments or a car-scrapping scheme. Additionally, an independent noise monitoring system - as outlined in this study - is a necessary prerequisite.
Findings of the study are published in detail by a final report (German only) which is available online via the Federal Environment Agency (UBA):