Are Dehumidifiers Safe Illustration

Are Dehumidifiers Safe? – Explained (2023)

by | Updated: Sep 19, 2023

The question of the safety of dehumidifiers is a topic of increasing concern as these devices become more common in homes and workplaces.

Used to reduce excessive humidity, dehumidifiers can improve indoor air quality, help prevent the growth of mold, and make living conditions more comfortable.

However, like any electrical appliance, dehumidifiers come with their own set of risks and precautions that should be observed.

This article breaks down the safety aspects of dehumidifiers, discussing factors such as fire risks, electrical concerns, and the impact on air quality in order to provide a comprehensive understanding of their operation.

Are Dehumidifiers Safe?

Dehumidifiers are generally safe when used according to manufacturer guidelines. However, they can pose risks such as electrical hazards or fire if not properly maintained or if faulty. It’s crucial to regularly inspect and clean the unit and to be aware of any unusual sounds or smells to ensure safe operation.

Are Dehumidifiers Safe Vector Illustration

How Does a Dehumidifier Work?

A dehumidifier works by removing excess moisture from the air to create a more comfortable indoor environment and to prevent the growth of mold and mildew.

The basic mechanics involve a fan that pulls air into the unit and over a set of cooled coils. As the air passes over these coils, the moisture in the air condenses into water, which is collected in a removable reservoir or drain pan.

The dry air is then rewarmed using the heat generated by the cooling process and released back into the room.

Some advanced units also come with features like filters to improve air quality, automatic humidity sensors, and energy-saving modes.

Is a Dehumidifier a Fire Risk?

A dehumidifier can pose a fire risk if it is improperly used, poorly maintained, or defective. Like any electrical appliance, faulty wiring, frayed cords, or electrical malfunctions within the unit can lead to overheating and potentially cause a fire.

There have been instances of dehumidifiers catching fire, often leading to recalls by the manufacturer. Therefore, it’s crucial to:

  • Regularly inspect the unit for any signs of wear, damage, or electrical issues.
  • Place the dehumidifier away from flammable materials and in well-ventilated spaces.
  • Follow all manufacturer guidelines for installation, operation, and maintenance.
  • Register your dehumidifier so that you’re notified in case of a product recall.
  • If your unit makes unusual noises, emits odd smells, or behaves erratically, discontinue use immediately and consult the manufacturer or a professional.

Note: By taking these precautions, you can significantly reduce the fire risk associated with using a dehumidifier.

Can You Run a Dehumidifier Constantly?

Running a dehumidifier constantly is technically possible but not generally recommended for several reasons:

  • Energy Consumption: Dehumidifiers can use a significant amount of electricity, so running one constantly can lead to high energy bills.
  • Wear and Tear: Constant operation will accelerate the wear and tear on the machine, potentially shortening its lifespan and increasing the likelihood of mechanical or electrical failures.
  • Over-drying: Running a dehumidifier all the time could make the air too dry, which can lead to issues like dry skin, irritated eyes, or an increase in static electricity.
  • Reservoir Overflow: If the dehumidifier is not self-draining, the water reservoir will need to be emptied regularly to prevent overflow, which could be impractical if running constantly.

Many modern dehumidifiers come with a built-in hygrometer that measures the room’s humidity level and automatically turns the unit on or off to maintain a target humidity level.

This feature allows for more efficient operation without the need for constant monitoring.

Note: Always refer to the manufacturer’s guidelines for recommended operating times and conditions to ensure both effective performance and safety.

Can Dehumidifiers Cause Health Problems?

While dehumidifiers are generally considered safe and can improve indoor air quality by reducing mold and mildew, they are not entirely without potential health concerns:

  • Over-drying the Air: Running a dehumidifier too much can excessively dry out the air, potentially leading to dry skin, irritated eyes, or respiratory issues.
  • Poor Maintenance: Failing to regularly clean the unit can result in mold and bacteria growth within the dehumidifier, which then get dispersed into the air you breathe.
  • Chemical Refrigerants: Some older or low-quality models may use harmful refrigerants that could pose a health risk if they leak.
  • Noise: Although not a direct health concern, the noise generated by some dehumidifiers can interfere with sleep or contribute to increased stress levels.
  • Electrical Hazards: Like any electrical appliance, a malfunctioning dehumidifier can be a fire risk or cause electrical shocks.
  • Contaminant Dispersion: Some dehumidifiers come with built-in ionizers or air purifiers. If these are not properly maintained or are of low quality, they could disperse harmful ozone or other contaminants into the air.
  • Incorrect Usage: Using a dehumidifier in a space that is already low in humidity can exacerbate respiratory issues for some individuals.

Note: It’s crucial to follow manufacturer guidelines and regularly maintain your dehumidifier to minimize these risks. If you have pre-existing health conditions or concerns, consult with a healthcare provider before using a dehumidifier.

How Dehumidifiers Can Be Good for Your Health

Dehumidifiers can offer several health benefits when used appropriately:

  • Mold and Mildew Prevention: High humidity levels can encourage the growth of mold and mildew, which are known allergens and irritants. Dehumidifiers can reduce humidity, thereby inhibiting this growth and improving air quality.
  • Reduced Allergens: Apart from mold, high humidity can also encourage the proliferation of dust mites, another common allergen. Lowering humidity makes the environment less hospitable for these allergens.
  • Respiratory Health: Damp, humid air can irritate the respiratory tract and exacerbate symptoms in people with asthma or respiratory issues. A dehumidifier can relieve these symptoms by creating a more comfortable living environment.
  • Comfort and Sleep: High humidity can interfere with the body’s ability to cool itself through perspiration, leading to discomfort and poor sleep quality. Dehumidifiers can help create a more comfortable environment conducive to sleep.
  • Skin Health: Excessive humidity can make skin feel sticky and uncomfortable, potentially leading to skin conditions like fungal infections. A dehumidifier can alleviate this discomfort.
  • Odor Reduction: Musty smells often accompany high humidity and are usually a sign of mold or mildew. Dehumidifiers can help eliminate these odors by tackling their root cause.
  • Preservation of Property: Excessive moisture can damage furniture, clothing, and even the structural elements of your home. While not a direct health benefit, preserving your environment can have an indirect positive effect on mental well-being.
  • Energy Efficiency: Lower humidity levels can make your home feel cooler, reducing the need for air conditioning and thus lowering energy costs, which in turn can reduce stress over household expenses.
  • Better Food Preservation: Lower humidity can help in extending the shelf life of some foods, which can be indirectly beneficial for your health by reducing spoilage and the risk of foodborne illnesses.

Note: By maintaining a balanced indoor humidity level, typically recommended between 30-50%, dehumidifiers can contribute to a healthier indoor environment.

When are Dehumidifiers Not Safe?

Dehumidifiers may not be safe under certain conditions:

  • Improper Maintenance: Failing to clean the unit regularly can lead to mold growth within the dehumidifier, contaminating the air.
  • Electrical Issues: Like any electrical appliance, a dehumidifier can become a fire hazard if it has a faulty motor, frayed cords, or loose plugs.
  • Overflowing Reservoir: If the water reservoir is not emptied regularly, it can overflow, creating a slip hazard or causing electrical malfunctions.
  • Poor Ventilation: Placing a dehumidifier in a small, enclosed space without good airflow can lead to overheating, increasing the risk of fire.
  • Chemical Refrigerants: Older or low-quality models might use chemical refrigerants that could leak, posing a health hazard.
  • Improper Placement: Units should not be placed near combustible materials, as they generate heat during operation.
  • Recalled Units: Occasionally, manufacturers recall units due to defects that could pose safety risks. Always register your appliance and keep up with product recalls.
  • Ignoring Manufacturer Guidelines: Not following the user manual for installation, maintenance, and operation could compromise the device’s safety.

Note: By being aware of these issues and taking preventative measures, you can minimize the risks associated with using a dehumidifier.

FAQs About Dehumidifier Safety

Can You Leave a Dehumidifier on Overnight?

Yes, you can leave a dehumidifier on overnight, but it’s important to follow the manufacturer’s safety guidelines and recommendations.

Many modern units come with safety features such as automatic shut-off when the water reservoir is full, and some have timers or hygrometers to regulate operation.

Ensure the unit is in good condition and placed in a well-ventilated area away from flammable materials.

Are Dehumidifiers Safe for Pets?

Generally, dehumidifiers are safe for pets when used according to manufacturer guidelines. However, be mindful of where the dehumidifier is placed to ensure pets can’t knock it over, and make sure cords are out of their reach to prevent chewing.

Also, consider the noise level of the unit, as some pets might be sensitive to the sound.

Is It Safe to Clean a Dehumidifier?

Yes, it is safe and recommended to clean a dehumidifier regularly. Accumulated moisture can lead to mold and bacteria growth within the unit, which can then be dispersed into the air.

Most units have removable reservoirs and filters that are easy to clean. Always unplug the unit before cleaning and follow the manufacturer’s cleaning instructions.

Will a Dehumidifier Dehydrate Me?

A dehumidifier removes excess moisture from the air, but it’s unlikely to dehydrate you unless the humidity levels are reduced to an extremely low level, which is uncommon in household settings.

However, excessively dry air could potentially cause dry skin or irritate your eyes and respiratory tract.

Is It Safe to Drink Dehumidifier Water?

It is not safe to drink water collected by a dehumidifier. While the water may appear clean, it can contain impurities like mold, bacteria, and dust from the air, as well as any chemicals used in the dehumidification process.

This water is not purified or treated for safe consumption and should be discarded or used for non-potable purposes like watering plants.

Is a Dehumidifier Safe for Babies?

Dehumidifiers can be safe for babies if used properly, but there are some precautions to take. Keep the device out of reach to prevent any accidental tipping over, and be cautious with humidity levels so as not to over-dry the air, as a baby’s skin is sensitive.

Always consult with a pediatrician for specific guidelines tailored to your child’s needs.

Can a Dehumidifier Affect Your Lungs?

A dehumidifier is generally beneficial for respiratory health by reducing allergens like mold and dust mites. However, if the air becomes too dry or if the unit is not properly maintained, it can potentially irritate the lungs and exacerbate respiratory issues.

Always maintain balanced humidity levels, typically between 30-50%, and keep the unit clean to avoid negative health effects.

When Should I Turn Off My Dehumidifier?

It’s advisable to turn off your dehumidifier when the humidity levels have reached a comfortable range, usually between 30-50%.

Most modern units come with a built-in hygrometer that can automatically turn off the unit when desired humidity levels are reached.

You should also turn off and unplug the unit when cleaning it or when leaving home for an extended period.

Final Thoughts

After examining the various safety aspects associated with the use of dehumidifiers, it’s clear that while these devices offer significant benefits in terms of improving indoor air quality and preventing mold growth, they are not without their risks.

Electrical faults and improper maintenance can turn these seemingly benign appliances into fire hazards or sources of poor air quality.

Therefore, it is crucial to follow manufacturer guidelines, regularly inspect and clean the unit, and be mindful of any unusual sounds or smells emanating from the device.

By taking these precautions, users can benefit from the advantages of dehumidifiers while minimizing the associated risks.

Written by:

John Landry, BS, RRT

John Landry is a registered respiratory therapist from Memphis, TN, and has a bachelor's degree in kinesiology. He enjoys using evidence-based research to help others breathe easier and live a healthier life.


  • Custovic A, Taggart SC, Kennaugh JH, Woodcock A. Portable dehumidifiers in the control of house dust mites and mite allergens. Clin Exp Allergy. 1995 Apr
  • Singh M, Jaiswal N. Dehumidifiers for chronic asthma. Cochrane Database Syst Rev. 2013 Jun 13

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