A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials

► We investigated the particles characteristics of different railway braking materials. ► A new index, airborne wear particle emission rate (AWPER), was introduced. ► The effects of key factors on the wear process and AWPER changes were discussed. ► An increase in the applied load caused an increase in the particle concentration. ► An increase in the sliding velocity caused an increase in the particle concentration.