Sub-ballast mats PURASYS SBM products are decoupling and protective mats under rail systems tested according to DIN 45673-5 (Mechanical vibration – Elastic elements of the superstructure of railway tracks). They reduce structure-borne noise and secondary airborne sound as well as vibration emissions. For ballasted tracks, the service life is extended by a lower and more even load. At the same time, it can protect engineering structures or sealings.