an apparatus and method for delivering ozone to a workpiece . in one embodiment , fluid is sprayed onto a workpiece placed in an ozone - rich environment . alternatively , ozone is mixed with the fluid prior to spraying the fluid onto the workpiece . when spraying the fluid , the invention pulses the fluid at desired rates to create a substantially uniform layer of ozone - rich fluid on the workpiece . in another embodiment , the workpiece is also slowly rotated during at least a portion of the time the layer of ozone - rich fluid is applied to the workpiece .