Of all the ways to use essential oils, simply smelling them is in some ways the simplest and most direct, most immediate, and most efficient. But there are many types of aroma diffuser, so which is best? What follows are my personal impressions.
Put simply, the purpose of a room diffuser is to deliver the essential oil to the receptors in our nose in as pure a form as possible, with as little waste as possible. Ideally this will mean not heating it, and certainly not overheating it.
Traditional Candle or Tea Light Diffusers
These are the diffusers which you will find in many gift shops. They include a water bath into which you put a few drops of essential oil and then light a candle or tea light underneath. This warms up the water and diffuses the essential oil into the room. If you like candles, they create a wonderful ambience. However it is impossible to regulate the temperature of the water and therefore the temperature of the essential oil. They often overheat and will burn the oil if you’re not careful, oxidising it and significantly decreasing the therapeutic value. There is also the potential hazard associated with naked flames.
A Nebuliser passes a jet of air across a small filament which is connected to a reservoir of essential oil. The air causes the oil to turn into tiny droplets which are then diffused into the room. In many ways this is the purest and most natural way to diffuse essential oils since there is no heating. The only downside is that they require a small electric motor to create the jet of air, so they are seldom completely silent. Oshadhi offers two of this type of nebuliser, the Crystal Diffuser with a wooden base, and the more portable Cool Breeze Microdiffuser which is powered by a 12 volt USB connector and which works effectively in a car (sitting in the coffee cup holder).
Over the last 15 years or so Ultrasonic Diffusers have become very popular and you will see them giving out puffs of ‘cool steam’ as part of their fragrancing effect. They look great, often have different coloured lights, are programmable and wonderfully convenient, easy to clean, safe, quiet and effective. However they are for some people a little controversial because of the way they work. What they do is to create a vibration of sound waves at frequencies greater than 20,000Hz. This is too high pitched for human hearing, but many animals, such as dogs, cats and bats can hear ultrasound. However the controversy is not because they may irritate your pets but rather because some people feel subtle negative effects from being exposed to ultrasound. Furthermore there is a feeling that they may disturb and adversely affect the subtle energetic value of the oil. We no longer offers these diffusers. I suppose it depends how much of a purist you are.
Fresh Air Fan Diffusers
Some diffusers require you to put some drops of oil on a pad through which a fan blows cool air. This sounds very simple, but in all honesty I have never found these to be particularly effective. They use up a lot of oil and don’t give much aroma. They also have an electric motor so are subject to noise issues.