Abstract: A powder spray apparatus and method for operating it comprise a spray booth having a floor. A spray gun is associated with the spray for directing a spray of powder of a particular color toward a workpiece. Overspray is redirected by limiting exhaust air from the flowing into an air-entrained powder separation system. An inlet to the separation system includes a sump for capturing powder from the floor of the spray booth when the floor is cleaned during a color changeover. The powder deposited in the sump is recirculated to a powder reservoir for later reuse.