SOUND EMISSION LIMITS FOR RAIL VEHICLES

The statistical evaluation of measured sound emission levels from individual rail vehicles enables a clear distinction to be made between disc-braked passenger vehicles with and without wheel absorbers and tread-braked vehicles equipped with cast-iron brake blocks. A retrofit programme for replacement of cast-iron blocks by composite (K-, L- or LL-) blocks seems feasible within the next five years. The performance and durability of the new brake blocks provides a substantial noise reduction at no or limited additional costs, depending on the need for new wheels. Additional wheel damping is desirable but not readily available at sufficiently low cost. Based on the experience from an experimental train equipped with a quiet locomotive, bogie shrouds and matching low-profile barriers along the track, sound emission limits are proposed which are described in two steps.