A waste collection unit for collecting waste material through a suction line during a medical procedure is described. The waste collection unit comprises a waste container configured to be in fluid communication with the suction line to collect the waste material during the medical procedure, said waste container having an internal surface defining a collection chamber. The waste collection unit further comprises a vacuum source in selective communication with said waste container for providing a vacuum in said waste container to draw the waste material into said waste container through the suction line, and a cleaning system comprising a liquid delivery device rotatably supported relative to said waste container, said liquid delivery device configured to direct liquid on said internal surface. Said cleaning system comprises an actuator operatively coupled to said liquid delivery device for rotating said liquid delivery device relative to said waste container to vary a direction in which the liquid is directed on said internal surface.
