Arrow Fat Left Icon Arrow Fat Right Icon Arrow Right Icon Cart Icon Close Circle Icon Expand Arrows Icon Facebook Icon Pinterest Icon Hamburger Icon Information Icon Down Arrow Icon Mail Icon Mini Cart Icon Person Icon Ruler Icon Search Icon Shirt Icon Triangle Icon Bag Icon Play Video
  • Diffusing Essential Oils- A Complete Guide
  • Post author
    Karissa Welch

Diffusing Essential Oils- A Complete Guide

Diffusing Essential Oils- A Complete Guide

Everything you need to know about diffusing Essential Oils!

Aroma diffusers have become incredibly popular in the last few years, reducing the use of chemical filled fragrances and allowing us to enjoy the amazing therapeutic benefits of essential oils. We have a wealth of options available, but do you know which diffuser is best, and how to diffuse safely?

Essential oils are powerful tools that have the ability to heal, and also to harm. There is so much misinformation floating around on the web, it’s hard to know what to trust. Add in the untrained advocates promoting excessive usage to sell more oils and the world of aromatherapy can be a minefield! We spoke with two of Australia's top clinical aromatherapists to pick their brains for their best tips and advice.

Essential oils are not 'one size fits all'. I encourage you to book a consult with an aromatherapist, they can help tailor an essential oil collection to perfectly suit your family's needs. You'll save money, get some great advice and stay safe as you begin your oily journey!

“It is tempting to think that because essential oils are natural, they are automatically safe.  However, this is not necessarily the case. Even with diffusion, a relatively safe method, there are some things to bear in mind to ensure that your use is both safe and effective.” Wendy Mackay.

In this complete guide, you’ll learn about choosing a diffuser, how to maintain it, usage guides, which essential oils should be used for specific uses and safety guidelines for adults, children and pets.

Let's Start with Types of Diffusers

There are four main types of aroma diffusers, in a wide range of styles and sizes.

1. Ultrasonic Cool Mist Diffuser

How- Uses ultrasonic vibrations to break up water and oil particles into an ultrafine mist.

Pros- Cost effective as only a few drops of essential oils added to the water reservoir can fragrance your home all day. Helps to humidify the air, easy to clean, is safe to use around children and comes in a wide range of styles.

Cons- If your home is prone to mold, the humidity added to the air won’t help. Diffusing oils like clove, cinnamon and eucalyptus occasionally will help prevent it becoming an issue.

2. Nebulising Diffuser

How- Uses a high velocity stream of pressurised air to atomise and disperse the oils as a fine mist.

Pros- Does not use water, produces a concentrated stream of essential oils ideal for short period therapeutic use.

Cons- Nebulisers use a large quantity of essential oils which can become very expensive, so are best suited for targeted aromatherapy needs. Can be fairly noisy.

3. Oil Burners

How- Relies on a heat source such as a candle or electric element to diffuse aroma.

Pros- Affordable, pretty, wide range of styles.

Cons- Denaturing (damaging) delicate essential oils with heat is avoided by anyone seeking therapeutic benefits from aromatherapy. Often wax melts and fragrance oils are used with this style of diffuser. These synthetic fragrances contain hormone disrupting chemicals and have no positive effect on your health. The risk of children around heated oils is another concern.

4. Evaporative Diffusers

How- Relies on evaporation from natural airflow to diffuse aroma and includes reed diffusers, ceramic and clay dishes.

Pros- Silent, does not require a power source, affordable. Very easy to DIY. Suited to small spaces such as toilets, bathrooms and cars.

Cons- Minimal therapeutic benefit and coverage. Can be an inefficient use of essential oils.

Depending on your specific needs, you’ll want to choose the right one for your purpose, or a combination.  As the main goal of using essential oils is to maximise the therapeutic benefit, I don’t recommend using diffusers that denature (damage) oils through heat.


Evaporative diffusers are very easy to DIY. String wooden beads, add a drop of oil and hang in the car. You can even use a wooden peg and clip to the air vent!

How big does my diffuser need to be?

The size of a diffuser is not really a true indication of it’s coverage and capacity. Diffusers range from 50 ml portable USB to large capacity 700 ml, with the average size being around 300 ml.  Again, you need to decide where you are positioning your diffuser, how long you would like it to run for and how much room it will take up.

How long do I run my diffuser?

Less is more. Good quality essential oils are expensive, we want to use them effectively and economically. Test with a couple of drops first, and increase the amount as needed. Have you noticed advocates encouraging people to diffuse all day long, adding up to 20 drops of oil into their diffuser? There is absolutely no reason for such excessive use. (Except encouraging you to buy more oils!)

Sonya Edmonds recommends, “ If diffusing into the air it is still advisable to do this intermittently. The general rule is 30-60 minutes on and the same time off. Firstly, it’s safer and secondly it enhances the effectiveness of the essential oils being used. Have you noticed how you can’t smell the aroma of diffused essential oils after some time? Our nervous system habituates to essential oils over time and we don’t recognise the smell anymore.”

What features should I look for?

The most important feature is an automatic safety shut-off. This is a built in feature that shuts down the diffuser when the water level is low to prevent damage and is a necessity in my opinion.

Adjustable timing is the next important feature to give you control over how long your diffuser runs for, and to prevent wasting expensive oils overnight or in an empty house! Look for short timing options from 1-3 hours and an intermittent function if possible.

Lighting options are also important, look for diffusers where the mist and lights operate independently to each other. This feature is particularly useful for childrens bedrooms where the diffuser is also used as a nightlight. While the light is able to be left on all night, it is not advised to diffuse for extended periods in a child’s room. Ideally, set the timer to 30 minutes-1 hour to help with a peaceful bedtime. The mist will turn off and the light remain on as a soft ambient light source. For adults who prefer a completely dark room to sleep, being able to turn the light off is a great feature!

TIP #3

Changing the oils in your diffuser? Use the leftover water and oil residue around the home! Some economical uses include bin odor spray, natural garden pest deterrent and toilet spray.

What should I put in my diffuser?

Anything you want... as long as they are pure essential oils! Citrus oils should be used in moderation as over time they may speed deterioration of the water reservoir.

Here’s a quick guide to some popular oils to diffuse. Remember these are not rules, just suggestions! Learn which oils have the most positive effect on you and experiment with combinations.



Ylang Ylang, Geranium, Lavender, Chamomile, Clary Sage, Tangerine, Bergamot, Patchouli, Lime, Mandarin.


Bergamot, Petitgrain, Frankincense, Rose, Lavender, Clary Sage, Sweet Orange, Palmarosa, Peppermint, Basil.


Lime, Sweet Orange, Grapefruit, Basil.


Rosemary, Peppermint, Lemon, Frankincense, Mandarin, Vetiver, Ginger, Sage.

Restful Sleep

Lavender, Bergamot, Vetiver, Rose, Ylang Ylang, Chamomile.


Sweet Orange, Clove, Cinnamon, Nutmeg, Lime.

Flu Season

Rosemary, Lemon, Clove, Cinnamon, Spruce, Eucalyptus, Lemon Myrtle, Marjoram.

Odor Removal

Lemongrass, Lemon, Spearmint, Lemon Myrtle, Petitgrain Orange, Eucalyptus, Tea Tree.

Child Safe Bedtime Blends 1-2 Drops

  1. Lavender & Cedarwood
  2. Chamomile, Rose & Lavender 


Add 1 drop of lemon, orange & peppermint essential oils to a tissue and tuck into the kids stinky sports bags, shoe box or school bag!

Grab a trio HERE

How to:


Empty weekly and wipe with a weak white vinegar solution. Be very gentle cleaning the ultrasonic plate. A small, soft brush is ideal. Wipe dry with a soft paper towel. (Tip leftover water into a spray bottle for an economical odor spray)


To maximise the coverage, position in a central location as high as possible. Be aware of the natural airflow in the space and use it to increase the coverage. Keep out of reach of small children.

Usage & Run Time-

Of course you can diffuse as much as you feel comfortable with, but for the most effective therapeutic benefits be sure to take a break. Just like any medicinal or holistic remedy, we don’t need to use our powerful essential oils constantly! Children and pets react differently to adults, and should be taken into account.

Sonya advises,

Having some fresh air in between diffusion of essential oils is always a good idea and adjust the quantity you’re using accordingly. Be aware of the size of the room you’re in and if windows and doors are open or closed.

As we mentioned, less is more. Wendy agrees and suggests,

“If the space is being used by children or anyone with allergies or sensitivities, you should also be cautions regarding the amount of essential oil that you use, (or whether you use any at all!). Again, start small.  And use any diffuser for a limited time, allowing for regular breaks. For example, using lavender to aid sleep in children may require just a drop of essential oil and the diffuser to be on for 30 minutes before bed and then turned off. It would not need to be on all night to be effective.”

Essential Oil Diffuser Usage Guide

Start with-

  • 50-100ml: 1-2 drops
  • 150-300ml: 2-3 drops
  • 350-500ml: 3-5 drops
  • >500ml: 4-7 drops  

TIP #5

Make chemical free, reusable drawer fresheners. Melt 100g wax in a double boiler, pour into silicone molds and add 5 drops essential oils to each mold.

Place hardened wax into cotton sachets and place into drawers for gorgeous scented clothes. When the scent is gone, melt and start again!

Get everything HERE

Diffusing Essential Oils Safely

Safety For Children.

Young children are far more sensitive to aromas as their immune system is not fully developed. They are less able to deal with the adverse effects that can arise from exposure to these amazing yet very powerful essential oils. Remember, less is more when dealing with children.

  • Do not diffuse overnight in children's bedrooms. Not only is this an ineffective use of oils, it can be harmful. Diffuse for 30 minutes before they go to bed, rather than while they are in bed.
  • Avoid diffusing in an enclosed space.
  • Dilute appropriately for topical use.
  • Cleaning with oils that are not considered child-safe- Yes you can still use eucalyptus, clove etc for cleaning. Remember to allow time for evaporation, wipe over surfaces with a clean damp cloth after cleaning to remove residue and avoid cleaning in enclosed spaces when children are present, or in spaces used by infants under 6 months. 

Oils to Avoid Completely- Under 6 Years.

Some oils to avoid are Anise, Eucalyptus, Clove, Fennel, Peppermint, Wintergreen, Oregano, Rosemary, Cinnamon Bark.  This is not a complete list, just a few of the most commonly used oils. It's always wise to research for yourself, and here's a great place to start. 

Safety For Pets.

Pets most sensitive to essential oils include birds, cats, small dogs, aquarium fish, brachycephalic breeds, pregnant and juvenile pets. Use extreme caution diffusing around these animals and research adverse effects to be aware of any warning signs.

Wendy says, "Another area of caution is diffusing if you have animals.  My usual suggestion is to be cautious with the amount of essential oil you use and for animals such as dogs or cats, always make sure that they have a space to “escape” to, whether this be outside or another area of the home.  For animals that are confined (fish, birds etc) I do not recommend diffusing in rooms where they are located."

Here are some more safety tips to consider.

  • Remove pets from the room when diffusing oils
  • Diffuse for short periods of time
  • Avoid using oils dangerous to pets
  • Rotate the oils in your diffuser regularly
  • Use a personal inhaler or apply topically instead 

Oils to avoid completely- Thyme, wintergreen, clove, cinnamon, tea tree, pine, birch, oregano, spruce.

This is not a complete list and I urge you to research from many independent sources. I’ve compiled a resource full of links to independent research studies, dilution charts and links to information from the various worldwide aromatherapy councils which is a great place to start! 

The most important thing of course is to enjoy bringing aromatherapy into our lives, and with a little common sense and safety we can do just that!




Sources & Contributors

Wendy Mackay is a professional accredited Aromatherapist and a member and past president of the International Aromatherapy and Aromatic Medicine Association (IAAMA), with over 20 years’ experience of using essential oils. Wendy is also the Founder and Director of Essence of Wellbeing Aromatherapy Products located on the beautiful Mornington Peninsula in Victoria, Australia. She is passionate about helping people to use essential oils safely and effectively.

Wendy has many useful articles on her website. One regarding safety I particularly recommend, you can check it out here.

Sonya holds a Diploma of Clinical Aromatherapy and Massage, is a Registered Nurse and Midwife, Certified Infant Massage Instructor and mum to two daughters. She is passionate about the natural healing properties of essential oils and has over 16 years’ experience in using aromatherapy to promote health and wellbeing. Drawing on her qualifications, experience and passion Sonya founded Mother Nurture Aromatherapy and Massage to cater for mothers, mothers to be and their families. She also has a strong interest in women’s health and practises at two Melbourne locations.

If you’re lucky enough to be in Melbourne, Sonya has a Practical Aromatherapy for Families workshop coming up.

Further Reading- Quick Links to Safety Resources

  • Post author
    Karissa Welch

Comments on this post (0)

Leave a comment