A particle blast cleaning apparatus incorporates a pressurized container which is pressurized by the transport gas upon start up through a feeder which does not comprise an airlock. The feeder introduces the blast media into the transport stream. At start up, the transport gas pressurizes the container, flowing upwardly through the feeder until the container is substantially pressurized and the flow substantially ceases. The feeder rotor may be configured to crush or grind the particles.