Abstract: Paint-laden air extracted from a paint-spraying booth is scrubbed by passing the paint-laden air together with a flow of water through at least one tube which extends downwards from the floor of the booth to a position spaced from the bottom of a water-container. A perforated baffle is located between the bottom of the water-container an an air velocity control opening associated with the tube, or one with each tube, the opening being of lesser cross-section than the tube and the perforations small as compared with the opening. A first stage separation of paint from air is effected by impingement against the baffle, a second stage by impingement of paint-laden air which passes through the perforations against water on the bottom of the water-container, and a third stage by passage of air through an annular curtain of water formed between the control opening and the surface of water in the water-container.