Abstract: An air cleaner for removing air entrained cooling oil mist, smoke and particulates which become air borne during machine tool cutting operations and the like thereby contaminating ambient air adjacent the machining and the like operations.The contaminated air is driven against a planar impingement plate arranged to be struck with a glancing blow of such force as to remove a substantial portion of the contaminates by impact.A series of cylindrical openings extend transversely through the impingement plate. The openings are sufficient in number to ensure continued flow through the cleaner. The plate is arranged at such an angle with respect to the air flow directed toward the plate that the openings appear to be elliptical to the air stream when the air first strikes the plate, thus effectively increasing the impingement surface area, but at the same time an adequate number of openings is provided through the impingement plate to maintained the desired air flow.