What Are Essential Oil Diffusers?

Variety of essential oil diffusers for blog

By Mark Piatt

Updated on April 25, 2019

So, you may be finding yourself asking “what are essential oil diffusers?” You may have heard of them but do not know what a diffuser is or how it works.  Let us take a few minutes and learn what are essential oil diffusers and why you should get one. 

What is an essential oil diffuser?

Essential oil diffusers are sometimes referred to as diffusers or aromatherapy diffusers.  For this article, we will refer to them as diffusers.  Technically, a diffuser is a device that is made to distribute something else.  Essential oil diffusers, therefore, are devices that disperse essential oils through different means. 

Using a diffuser is an enjoyable and effective way of experiencing aromatherapy in your home because most essential oils emit a pleasant scent into the air. The diffuser fills a room or area with the fragrance of essential oil.  These oils may be used strictly for the aroma or they may be used because of their potential health benefits.  The fine vapor created by the diffuser allows the body to gently absorb the compounds in the essential oil through the respiratory system. 

Using diffusers is an excellent alternative to those sprays and plugins that use artificially made chemicals to produce and dispense their smells.  There is an assortment of methods diffusers employ to diffuse essential oils, which we will be exploring.

Types of diffusers

There are a variety of diffusers, but the main 4 types of essential oil diffusers are Ultrasonic diffusers, Nebulizing diffusers, Heat diffusers, and Evaporative diffusers.

The ultrasonic diffuser

The ultrasonic diffuser is the most popular type of diffuser. This type of diffuser is ideal for small spaces up to about 500 square feet depending on the size of the diffuser.  Ultrasonic diffusers use water with a few drops of essential oil.  Typically, you use about 5 drops for every 100 ml of water. 

By using electronic frequencies for creating vibrations in the water, ultrasonic diffusers allow the essential oils to disperse into the air.  The result is a fine mist that can be inhaled very safely and effectively.  Ultrasonic diffusers are an effective means of distributing the aroma of essential oils around a room or small area.

Ultrasonic diffusers usually run very quietly making them perfect for use in meditating, relaxing, sleeping, or whenever you wish.  However, this device uses water, so the concentration of the oil itself is not too strong or potent. 

You will find though that the aroma is subtle but noticeable.  The power of the aroma also depends on the essential oil being diffused.  Top note essential oils such as lemon, orange, and grapefruit are extremely volatile and faint in smell.  These oils typically require a few more drops than normal to achieve the effect you seek or you may need to replenish these oils more often than usual.   

Using an ultrasonic diffuser comes down to personal preference.  For some people, the ultrasonic diffuser does not produce enough of an aroma.  For others who do not enjoy overwhelming smells or want their oils to last longer, the ultrasonic diffuser produces the perfect amount of aroma.  

The good thing about ultrasonic diffusers is they can also be used as a small humidifier. This means they are useful in winter and dry environments.  Because no heat is involved in the process, the integrity of the oil is preserved, giving you the maximum benefit of the essential oil.  They are also usually less expensive compared to a scented candle and are a healthier choice.  Because ultrasonic diffusers use a small number of essential oils compared to nebulizing diffusers, they are less expensive to use compared to nebulizing diffusers.

Finally, the ultrasonic diffuser requires regular cleaning and maintenance.  Also keep in mind that because of the technology being employed, these types of diffusers eventually burn out.  But ultrasonic diffusers are definitely worth the investment if you are interested in scenting your home naturally and healthily.

The nebulizer

They are the most powerful diffusers with solid operation and easy implementation. You don’t need heat or water. Simply attach the essential oil bottle to the device and you are good to go.  Since the essential oil attaches directly to the device, the content and intensity of the spray are quite thick and solid.

The device will make sure the oil gets into the air, utilizing a special atomizer to create fine airborne particles of the oil.  If the diffuser is being used for health conditions, this type of diffuser is the best because it will give you a powerful and continuous source of essential oil.  The good thing about this device is that essential oil bottles attach directly to the diffuser, so there is no fuss. Since it doesn’t use heat or water, nebulizing diffusers require no additional prepping.  If taken care of, these types of diffusers can last a lifetime.

This is the device to use if a strong concentration of essential oil is desired.  Nebulizing diffusers usually also come with timers, allowing you to set up and adjust the operational time.  However, they can be noisy, especially when compared to an ultrasonic diffuser. Since the concentration of the oil is quite strong and potent, you will use much more essential oil.  For this reason, nebulizing diffusers are costlier than ultrasonic diffusers.  These are a good choice for larger rooms. 

For some people, the nebulizing diffuser is too intense and can cause them to get a headache within minutes.  For this reason, some people will only use them for a few minutes and when there is a real need for one such as when you have congestion or if you wish to use essential oils that are capable of killing bacteria or mold.

Evaporative diffusers

This device generally uses a filter or pad and a fan. The essential oil is dropped on the pad or filter, and then the fan will gently blow across the pad, causing the oil to evaporate (generally quicker than normal), and then the scent and the oil will be circulated around the room.  They are usually very efficient at dispersing aromas of thicker oils such as sandalwood and myrrh.  Depending on the size of the diffuser, they can fragrance a large area and some can be powered by batteries, making them very portable. 

However, one major drawback of this mechanism is that if you are using the evaporative diffuser for health reasons, the lighter components of the oil will be higher at the beginning while the heavier components will be delivered later, making the benefit of the essential oil a little more difficult to achieve.   Also, for those diffusers that require an absorbent pad, you will need to periodically replace the aroma pads.  Some can be a little noisy. 

Heat diffusers

It is almost the same as the evaporative device but uses heat to disburse the essential oil.  The heat could either be from an electrical source or a flame.  The main drawback is the chemical compounds found in essential oils tend to change when they are heated, which means you may not get all the benefits you are expecting. 

Thicker essential oils such as sandalwood are good candidates to use with a heat diffuser.  Some heat diffusers use a high level of heat that can make the aroma intense.  If you are using the essential oil strictly for the aroma, these can be a good choice.  But if you are looking for the healing effects of the essential oil, heat diffusers are a poor choice since they alter the chemical makeup of the essential oil.  Finally, heat diffusers are relatively inexpensive and are quiet to use.

Other types of diffusers

A few other types of diffusers exist. The candle diffuser can be less expensive than a nebulizer.  But because of the open flame, there is some inherent danger to using candle diffusers.  Terracotta and sandstone diffusers come in an array of attractive sizes and styles.  You usually pour the oil into the diffuser or on a pad.  The aroma permeates through the pot and disperses throughout the room using natural currents.  The one disadvantage is the smell becomes less potent as time goes by.  Lamp ring diffusers have a lip that wraps around a light bulb. The oil is placed on the lip and the heat of the bulb causes the essential oil aroma to permeate. 

How long should you use your diffuser?

That depends.  There is no standard recommendation for how long to diffuse your essential oils because there are many factors at play.  Generally, diffusing essential oils is considered safe.  Keep in mind that even though essential oils are all-natural, they are made up of many compounds.  Some of these compounds have the potential of causing negative side effects.  Blasting your diffuser all day and night could cause an over-exposure that could lead to headaches, asthma, high blood pressure, increased heart rate, and other health factors.

If you are using your diffuser for health benefits, some aromatherapists suggest using your diffuser for no more than an hour at a time or 3 times a day for no more than 30 minutes at a time.  Of course, many diffusers have various timers.  Some shut themselves off and on periodically, reducing the number of essential oils being diffused.  Some will shut themselves off after a set time. 

If you are using your diffuser for the scent, then the decision is more about your taste.  Keep in mind that you can become immune to the scent.  You may no longer smell the scent, but if someone were to walk into the room, they would instantly smell the aroma. 

Some oils work better than others to cover up “those” smells.  Tea tree and lemon oil are two particularly good essential oils for covering up bad smells.  Remember that some essential oils have safety issues.  Educate yourself and know what you are using.

Different essential oils stay in the air longer than other oils.  Light essential oils such as Peppermint, lavender, orange, and lemon will usually dissipate within an hour or two.  Middle note essential oils such as rosemary, chamomile, and geranium will last in the air for between two and four hours.  And finally, heavy essential oils such as sandalwood, cedarwood, and myrrh may linger for many hours or even days. 

The environment can also affect how long the aroma lasts.  If you are in an area with a large amount of air circulation like from an air conditioner, the aroma will dissipate much more quickly.  During the summer months or if your room is warm, the essential oils may dissipate quicker than if they are in a cold room.  The amount of humidity in the air can also affect how long the aromas last. 

As a best use practice, for every 100 ml of water used in an ultrasonic diffuser, use 3-5 drops of essential oil.  You may adjust that depending on the note of the oil.  Usually, your diffuser will come with instructions on how much essential oil you should use.

Also, the quality and concentration of the essential oil are everything.  Is the fragrance natural, synthetic, etc?  Not all essential oils are created equal.  If an essential oil is 100% pure essential oil, the aroma will be stronger.  The aroma can differ based on the species, growing season, soil, extracting method, age, etc.    

Are diffusers expensive to use?

When you look at the prices for essential oils, at first glance using essential oils may seem more expensive than using other alternatives such as scented candles.  Let us take a close look at these costs.  There are about 20 drops per milliliter of essential oil.  A 1-ounce bottle has 29.5 milliliters which comes out to about 591 drops per 1-ounce bottle.  Once you know this information, you can calculate how much it costs you to diffuse your essential oil.

For example, let us say you can purchase a high-quality 1-ounce bottle of lavender for about $30, less if you purchase a cheap bottle, which we do not recommend.  That works out to $.05 per drop.  In your ultrasonic diffuser, if you use 5 drops in a 100 ml diffuser that will last for about 6 hours, that is slightly over  $.04 an hour.  Not too bad. 

As a comparison, say you purchase a 20-ounce lavender Yankee Candle for $20 rated at 110-150 hours.  At 150 hours, that works out to $.13 an hour.  That is nearly 3 times as much as using a high-quality essential oil.  Plus, you do not get the nasty soot and dangers of having an open flame.    

Cleaning your diffuser

For ultrasonic diffusers, you should give your diffuser a cleaning at least once a week.  Wiping down your diffuser with vinegar will help dissipate some of the aromas.  Some people will diffuse a tablespoon of vinegar with water for 15-60 minutes.  Others will let the vinegar sit for 30 minutes and then dump it.  There are also cleaning tablets that dissolve in the water and remove any oil buildup.  

Follow the recommendations that come with your particular diffuser.  If you still have water remaining in your diffuser and you plan to use it again later that day or even the next day, there is no reason to dump out the water.  Even if you are going to use fresh essential oil, the aroma of the lingering essential oil usually does not seem to affect the aroma of the new essential oil. 

Safety concerns

Most essential oils are safe to use when diffusing.  Certain oils are not safe to use around babies and young children, pregnant or nursing mothers, and pets.  Most of these concerns refer to using the oils topically or ingestion, but you need to educate yourself if you are going to diffuse oils around these groups.  There are very few clinical studies and opinions vary widely. For this reason, you should err on the side of caution. You really should not be using a diffuser in public areas such as offices, stores, or even at home if you have company. 

What benefits do diffusers have?

There can be many benefits from helping people breathe, sleep, relax, uplift their mood, cover bad smells, improve mental clarity, etc.  A nice holiday ambiance can be created by diffusing pine, nutmeg, and cinnamon.  A refreshing aroma can be created with spearmint, peppermint, and frankincense.  Using orange is a nice uplifting smell.  An entire book can be written on the subject.  For this reason, diffusers have endless possibilities for supporting your health and wellbeing, and for creating the right ambiance within your area.  Now go forth and start diffusing.  Enjoy yourself and the wonderful aromas you can create.



Information provided in this description is for educational purposes only.  For possible treatments of physical or mental diseases, please seek a trained and licensed health professional.  Enchanted Aromatics is not responsible for any adverse affects resulting from the use of any suggestions, products, preparations, or procedures mentioned or from following historical uses of essential oils.

This site uses cookies to offer you a better browsing experience. By browsing this website, you agree to our use of cookies.