Basically rolling noise in railways is created by rough wheels and tracks. If both can be kept smooth, noise can be reduced significantly. Smooth wheels can be achieved by replacing cast-iron brake-blocks with composite brake blocks. Currently two types of composite brake blocks are being discussed: K- and LL-blocks. K-blocks probably have a higher noise reduction than LL-blocks, but require adapting the braking system while wagons can be retrofitted with LL-blocks without adapting the braking system. Several economic studies show that railway noise reduction in retrofitting the freight wagon fleet with composite brake blocks has the highest cost-effectiveness. Also, if composite brake blocks are combined with other measures, the overall cost-effectiveness is increased. However in many European countries extensive noise barrier construction programmes are being implemented. Due to the harsh competitive transport market, retrofitting is not possible without external financial support for railway operators. Currently EU funding is only likely for pilot or demonstrator projects. Direct national subsidies are the most efficient short term solution. Differential track access charges are considered too complicated for a short term implementation, they may prove useful to maintain a silent freight fleet in the long term.
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