Ultrasonic water diffusers were originally developed as foggers or misting fountains that simply convert water into mist or vapor and had nothing to do with essential oil. Many of these units were sold because they were neat and attractive.
Then it was discovered that adding a few drops of essential oil to the water would make it smell nice. It was marketed as an "essential oil diffuser" and over time consumers had come to believe that this was true oil diffusion. Unfortunately, ultrasonic diffusers do not perform as advertised. The actual results show they provide very little aromatherapy.
It must have been a huge breakthrough in marketing campaigns, because the idea exploded into a multitude of products directed to the Essential Oil and Aromatherapy industries. Ultrasonics became a commodity because they were cheap and had no regulation. At first the units were good quality, but as the demand increased, China provided cheaper, low quality knockoffs to be sold dirt cheap. This kicked off the Race to the Bottom to get the lowest cost diffuser by cutting down the quality as much as possible.
Test Results and Comparisons of the Airborne Particles
Essential oil diffusers are absolutely NOT all alike, and now there is scientific proof. ESIP, LLC commissioned the chemistry department at Southern Utah University to research, test, and compare the airborne particles of nebulizing, ultrasonic, and fan diffusers. This is what they discovered. The Nebulizing / Atomizing method of diffusing is far more therapeutic and is more worth your money. The ultrasonic diffusers are simply “room-scenters”. Do not rely on random and out-of-date internet comments and opinions unless they are backed by scientific DATA and RESEARCH. This short video recaps the lab test and results conducted by the aforementioned entity.
The data shows that diffusing with an Atomizing / Nebulizing diffuser not only diffuses FOUR TIMES more particles into the air, but the micro-particles stay suspended in the air 55 MINUTES LONGER than any other method. That's almost FOUR TIMES longer! By using an Atomizing / Nebulizing diffuser, you’re getting 100% therapeutic benefit from the oils because the oil is not diluted. They are fully intact, with all of the natural healing properties of the essential oils. Also, we now understand that running the Atomizing / Nebulizing diffusers on HIGH pressure output and for SHORTER time increments is perfectly adequate because the oils remain suspended longer; thereby conserving the essential oil usage.