What type of nebulizers are there?
There are two main types of nebulizers: jet and ultrasonic devices. Jet nebulizers form droplets by using a compressor to deliver a pressurized jet stream of air down a narrow tube and through an opening. This creates a vacuum (through the Venturi effect), thus drawing liquid from a reservoir. The resultant small droplets of liquid are propelled out of the machine by the continued jet stream. Ultrasonic nebulizers produce aerosolized droplets using high-frequency sound waves generated by a special crystal. Liquid drug is usually delivered to the crystal, where it forms a thin layer. Electricity excites the crystals, causing them to vibrate at extremely high frequency. This vibration forces the thin liquid layer through an adjacent mesh, creating a fine mist. Droplet size varies with the frequency of the sound waves created by the vibrating crystals.
