Nozzle device and nozzle for atomisation and/or filtration as well as methods for using the same. The present invention relates to a nozzle and nozzle device for atomisation, in particular a micro-machined reinforced nozzle plate, that may produce small liquid droplets in air (spray) or into a liquid (emulsion) with a narrow droplet size distribution and to make small air bubbles into a liquid (foam) and to methods of making the same. The invention is further related to a nozzle part for filtration as well as means and methods to facilitate atomisation and filtration.