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  • Writer's pictureGina Scrofano

Are Humidifiers Safe For Pets?

Dog, Humidifier, Interior Room

Cold weather, wind and heated interiors can cause our skin and nasal passages to become quite dry. The same goes for our pets, which can lead to stuffy noses and itchy skin. Our pets also sometimes have a short breathing passage or are diagnosed with illnesses that cause symptoms, leaving us searching for ways to alleviate their discomfort. Humidifiers can be a good way to provide much-needed relief, as they return moisture to the air and help pets breathe. We additionally feel warmer in humid air, allowing us to keep our thermostats lower, which also prevents dryness. However, there are risks and important factors to consider when it comes to humidifiers. Below is some information to help you decide if using a humidifier is the right choice for you and your pet.

1. Consult Your Vet & Consider Underlying Causes

It is important to note that dry skin, excessive itching, a runny or stuffy (noisy, congested, inflamed) nose or sinuses can be symptoms of underlying health issues, such as mites, allergies, malnutrition, respiratory infection, virus, tooth abscess, a foreign object in the nose, polyps, tumors, or other illnesses, diseases, or disorders. Be sure to consult your veterinarian as soon as absolutely possible to confirm dry air is the sole culprit of your pet's symptoms, and if a humidifier is recommended. If there is labored or abnormally rapid breathing (panting, open mouth/beak breathing, even while at rest), bluish, purple, or whitish gums, seek veterinary care immediately.

2. 'White Dust' - Disbursement Of Contaminants

All water has varying mineral levels depending on where it was extracted and how it was processed. You may have heard the term 'hard water.' That's in reference to minerals; the more minerals, the harder the water. When minerals are dispersed into the air by humidifiers, it appears as 'white dust;' the harder the water, the more dust. Not only is the dust annoying to clean, but it can be harmful. Dispersement of minerals can impact air quality as it increases the potential of allergens, contaminants and bacterial growth. Additionally, lime deposits created by minerals can build-up in the water tank, creating a perfect surface for bacteria and mold. However, there are ways to help minimize those air contaminants and prevent bacteria, which are discussed below.

3. Types of Humidifiers

Ultrasonic Humdifier

Ultrasonic Humidifiers

*'White Dust' & Sound Frequency Risks

These humidifiers use high-frequency sound vibrations to turn water into mist. Because it expells mist as opposed to steam, there is no risk of scalding. However, there are also no filters, which means they disperse a decent amount of 'white dust' and potential allergens, also creating a higher risk for bacteria. Ultrasonic means a frequency greater than 20,000 Hz, which is the upper limit of human hearing. Meaning, they're approximately too high for us to hear. Therefore, these humidifiers seem quieter to humans than others. However, animals can hear higher frequencies than us; dogs and cats up to approximately 65,000 Hz. Depending on the frequency of the humidifier, it's possible that our pets will hear it, potentially frustrating or frightening them. If shopping for an ultrasonic humidifier, be sure to check the frequency on the box and take that into consideration.

Impeller Humidifier

*'White Dust' Risks

Also sometimes referred to as 'cool-mist' humidifiers, these have a rapidly rotating disc that impels water against a diffuser, breaking the water into droplets which float into the air. These humidifiers do not have filters, which causes 'white dust' and the spread of mineral deposits, making bacteria and mold a higher-risk than with others.

Warm-Mist Humidifier

Vaporizers / Steam / Warm-Mist Humidifiers *Potentially Increased Burn & Fire Risks Depending on Type - Warm-Mist Preferred & Most Recommended Overall

These are popular, as the portable versions are inexpensive and can provide heat and humidity simultaneously. Vaporizers convert water into steam, a process that kills microorganisms, so they're also often filter-free. While there's a decreased risk of bacteria, there is an increased risk of burn, injury or fire due to the heat the appliance must generate to function. Vaporizers are often hot to the touch and the steam can also scold a pet that gets too close. More recent models, often referred to as 'warm-mist' humidifiers, are perhaps one of the best options for overall use, performance, and maintenance. Warm-mist humidifiers release warm or hot air rather than scolding, which makes them less hot to the touch and reduces the risk of a burn - however, it is still important to keep pets clear from the mist to prevent injury. This could pose an increased risk to animals who like to climb onto counters or dressers - so extra precautions should be taken in those cases. These humidifiers sometimes also come with attachments for the use of 'medicated cups' or essential oils, which are dangerous for pets (see number 8 below). If this type of humidifier is chosen, be certain not to use any oils or additives, that it is used under direct supervision to ensure it does not overheat or become a fire hazard, and that it is out of the reach of pets. These humidifiers have no filter, so they cost less to maintain, however, the minerals in water can clog them - an issue often prevented with routine cleaning.

Evaporative Humidifier

Evaporative Humidifiers

*Requires Filter Replacement

Perhaps the most long-standing and common type, these humidify an area by absorbing water via a wick filter and sending moisture into the air with a fan. Some compact versions don't have a filter, but most evaporative humidifiers do. Those filters reduce 'white dust,' as they trap minerals and prevent them from being dispersed into the air. However, in addition to the need for cleaning, those filters must be replaced frequently to prevent mineral buildup and bacteria. Some evaporative humidifiers are referred to as 'cool-mist' humidifiers.

4. Avoiding Bacteria / Maintenance Requirements

Humidifiers are high-maintenance appliances. They require routine cleaning, disinfecting and filter replacements to prevent bacteria, mold, and allergens from building up and being dispersed into the air. Many say that weekly cleaning is necessary. If you use a humidifier, be prepared to put in some work and cover the expense of filter replacements (if the appliance has them). Always follow the manufacturer's maintenance guidelines, at the very least, to ensure you do not inadvertently make you and your pet sick.

How To Clean A Humidifier - Step by Step

Note: White Vinegar may be substituted for bleach

5. Using Distilled Water

Distilled water (AKA 'purified water') has been boiled into vapor, then condensed back into a liquid, greatly reducing the number of minerals, thus also reducing the 'white dust' and increasing air quality from humidifiers. However, it does not make water 100% mineral free, nor does it eliminate the need for cleaning. No matter what we do, water will be wet, and where there is moisture, there will be bacteria if not prevented. While distilled water is recommended for better air quality, routine cleaning is still necessary.

6. Unplug When Unsupervised - Prevent Fires & Injuries

Regardless of the humidifier type or 'auto shut-off' features, it is essential to turn them off and unplug them while unsupervised or not home to prevent putting beloved pets in danger of fire or injuries.

7. When Not Using & Storage

Keep your humidifier clean and dry while not in use. Never store a wet humidifier (or with a damp filter) and without cleaning, disinfecting and drying it thoroughly. Be sure to also clean it again before re-use after storage. You can never be too careful when it comes to safeguarding against bacteria, which can grow where there's even the tiniest bit of moisture.

8. Avoid Additives & Oils

While essential oils are most toxic to pets in their concentrated form, their use in humidifiers can still pose a health risk for our pets, as can 'medicated cups' or other additives. This is especially true for birds as they have sensitive respiratory tracts, as well as pets with a history of breathing or sinus problems. Pets can also come into direct contact if they knock over the appliance accidentally. When it comes to alleviating our pet's symptoms from dryness, a humidifier works wonders all on its own, no additives needed.

Essential Oils - Pet Risks

9. Avoid Too Much Humidity / Use A Hygrometer

Adequate indoor humidity for humans is approximately 30% to 60%, according to the Environmental Protection Agency. However, proper humidity may vary for pets depending on species, and their individual needs. Birds and ferrets are particularly sensitive to humidity, and of course, reptile enclosures should be regulated separately. Consult your veterinarian to determine what is best. Hygrometers are recommended to measure humidity levels and can be purchased from home improvement stores and online retailers. Too much humidity can impact the comfort of our pets, cause difficulty breathing, and also lead to viruses, bacteria, and mold. Condensation on the furniture or walls and a musty smell are signs that the humidity is too high.

10. Increasing Humidity Without A Humidifier

Straight Twist, Metal Bowl, Water, Heat Register, Vent, Humidity
  • Boil water on the stove (never while unsupervised)

  • Hang your clothes to dry

  • Get some non-toxic houseplants*

  • Leave the bathroom door open while you shower

  • Open the dishwasher just before the dry cycle and let the dishes air dry

  • Boil water in a pot or teakettle when making tea.

  • Distribute large bowls of fresh water throughout the house. Place them on top or in front of floor registers, heating vents, radiators, or windowsills. It helps if placed near heat, or where there is a draft, allowing air to pass over the surface of the water. If near heat, use metal or ceramic 'heat-safe' bowls. Also be sure to keep the water fresh and the bowls clean to prevent allergens and bacteria.

  • Put a milk crate top-down over a floor heat register or vent where the heated air is blown into your room. Take a damp towel and lay it (unfolded) on the crate. When the air comes into the room, it will be forced to go through the damp towel, adding moisture to the air. Be sure to routinely switch out with a fresh towel to prevent bacteria and mold.

*Toxic/Non-Toxic Plants - For Cats

*Toxic/Non-Toxic Plants - For Dogs

Straight Twist, Logo, Animal Welfare


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