Abstract: Compressed air driven vacuum pump assembly wherein the energy contained in compressed air is used to create a vacuum flow within a housing unit. Preferably, the modular housing unit includes a series of axially aligned air nozzles to provide a substantially straight air flow path through the housing unit. A series of axially aligned vacuum structures provide a vacuum flow path that is substantially parallel to the air flow path. The capacity of the vacuum pump is increased by elongating and enlarging the air and vacuum flow paths by means of the addition of modular housing units. The vacuum pump assembly includes an external muffler to dampen the air flow as it exits the housing unit.