Continued in Overview tab.
Diffusion also helps purify the entire environment by distributing the anti-bacterial and anti-viral essential oils to all surfaces within a room, reducing the risk of infections being transmitted.
The best diffusers transport the essential oil molecules in a complete form without modification. The smaller the droplets of oil produced, the longer that they stay suspended in the air and the more they will travel throughout the room. The non-heated diffuser is best, because all notes are transported equally. With a heated diffuser the lighter molecules diffuse first, leaving the heavier notes behind.
Because the olfactory system tends to "overload" it's best to diffuse intermittently. After about 15 to 30 minutes you won't be able to smell the EO any more and you are wasting oil. You can either change to a different scent, or simply wait until your olfactory sensors clear out. On the other hand, if you are treating a respiratory problem or purifying an environment, it may be desirable to run the diffuser continuously on a lower setting. Even though you won't be able to smell it, you are still getting a benefit from having the molecules introduced into your system.
Safety Precautions: Because some essential oils are inflammable, be very careful when using them around open flames, such as candles or near the fireplace. When using a "Tea Light Burner" it is best to place some hot water in the bowl and then sprinkle a few drops of essential oil on top of the water before lighting the candle. That way if you spill it there is likelihood of causing a fire.