A nozzle comprises a lower nozzle plate including a lower impingement surface formed therein, at least one fluid intake port disposed at an inner end of the lower impingement surface, and an upper nozzle plate including an upper impingement surface formed therein and an upper orifice edge disposed along an outer end of the upper impingement surface. The nozzle includes a seal configured for sealing the lower nozzle plate to the upper nozzle plate, such that the lower and upper impingement surfaces are opposed toward one another, thereby forming a fluid channel between the impingement surfaces, directing pressurized fluid from the at least one fluid intake port to a slotted orifice formed between the opposed lower and upper orifice edges. The nozzle includes a droplet size adjustment mechanism configured for attachment to the upper and lower nozzle plates for selectively controlling fluid droplet size ejected from the slotted orifice.