The invention relates to an air supply facility (10) for mounting on a rail vehicle or a utility vehicle, comprising a compressor device (12) for producing compressed air, which is arranged in a process air line (14) between a process air inlet (16) and a compressed air outlet (18), a cooling device (24) for cooling the compressor device (12) and/or the process air line (14), and a fan device (26)for blowing cooling air towards the cooling device (24) or sucking cooling air through the cooling device (24) which is arranged in a cooling air channel (38) between a cooling air inlet (28) and a cooling air outlet (30). The aim of the invention is to be able to reliably use the air supply facility (10) even in areas where particles such as sand, dust and/or water are to be found in the surrounding air. To this end, the air supply facility (10) also comprises a grit separator (36) arranged upstream, in relation to the air flow, of the process air inlet (16) and/or the cooling air inlet (28), for separating particles from the surrounding air sucked through a surrounding air inlet (32).