Abstract: An improvement in reduction of particle size of painting and coating particles is achieved by providing a tapered channel(s) in the cylindrical wall radially of the spray apparatus' nozzle head, which is a wall adjacent the nozzle outlet slit. Using the "Bernoulli Principle," its venturi feature achieves a movement and acceleration of ambient air to intermix with the paint particles being dispensed through the nozzle outlet slit. The tapered channel(s) extends radially inwardly from an air inlet opening on the exterior face of the wall, fully through the wall, and into a downstream air outlet opening on the interior of the wall face, the tapering of the channel being of a downstream size-reducing nature.