Technology, Measures, & Innovation

Understanding Your Dehumidifier & Air Purifier

When it comes to leading our healthiest, happiest lives, breathing clean air is of key importance. Air purifiers and dehumidifiers can help you maintain the quality of the air in your home, keeping you safer from airborne diseases and mold conditions while also decreasing the impacts of potential asthma and allergy triggers.

Understanding Your Dehumidifier

Dehumidifiers work to change a room or spaces humidity level by remove access moisture from the air. This can help reduce allergens, prevent mold growth, and improve indoor air quality in damp spaces. The moisture from the air must go somewhere and dehumidifiers typically have a storage tank that collects the moisture and stores it until full, stopping operation. Others may have an option to attach a hose that can be directed to a sink, floor drain, or sump pump for drainage. ENERGY STAR certified dehumidifiers have more efficient refrigeration coils, compressors, and fans, compared to conventional models, which means they use less energy to remove moisture.

Person changing out the water tank on a small dehumidifier.

How to Choose the Right Size Dehumidifier

A dehumidifier pulls moisture from the air, helping to reduce humidity and improve the quality of air, but it should be properly sized for the needs of your home. A dehumidifier that is too large will waste energy and lead to higher electricity bills. Bigger isn’t always better. The size you'll need depends on the size of your room (or basement) and the amount of moisture present in the air. Use the list below to estimate the capacity you are looking for.

Dampness Scale

Dampness Scale
Room Dampness	500 sq. ft. area	1,000 sq. ft. area	1,500 sq. ft. area	2,000 sq. ft. area
Moderately Damp - space feels damp and smells musty only in warm, humid weather.	10 pints per 24 hours	14 pints per 24 hours	18 pints per 24 hours	22 pints per 24 hours
Very Damp - space always feels damp and smells musty.	10 pints per 24 hours	17 pints per 24 hours	22 pints per 24 hours	27 pints per 24 hours
Wet - feels and smells wet. Seepage occurs. Mold and mildew growing on surface.	14 pints per 24 hours	20 pints per 24 hours	26 pints per 24 hours	32 pints per 24 hours

Other Ways to Reduce Humidity in Your Home

Keep basement and crawl spaces sealed off from the outdoors.
Install gutters and divert roof runoff away from the foundation.
Improve grades around the foundation to drain water away.
Cover dirt floors in crawl spaces and basements with heavy-duty plastic.
Ensure that clothes dryers are properly vented to the outdoors.
Wrap cold water pipes with pipe insulation to eliminate sweating.
Use exhaust ventilation to remove moisture generated by showering, bathing, and cooking.
Reduce the number of plants in humid areas.
Do not store wet firewood in the basement.
Do not open basement windows and doors in the summer to dry out the basement. This can make the problem worse by allowing moist outdoor air into your cool basement, causing increased condensation.

Understanding Your Air Purifier

Along with dehumidifiers, air purifiers can improve your home’s indoor air quality and reduce allergens. Through an air intake and filtration process that can contain multiple filters including ultraviolet (UV), high-efficiency particulate air (HEPA), and activated carbon filters; air purifiers remove air pollutants from the air your home, releasing the clean air back into the room. These air pollutants can come from cooking, cleaning, secondhand smoke, outdoors, as well as other sources. They can also be in the form of particles or gases that can contain volatile organic compounds (VOCs) that can come from chemicals in paints, cleaning supplies, and some building materials. These can have short- and long-term health effects. ENERGY STAR models are more energy-efficient than standard models and save you both energy and money while increasing your indoor air quality.

An air purifier at the foot of a white bed.

What is CADR?

Clean Air Delivery Rate (CADR) is a certified measurement system that shows how effective an air purifying device is at removing particulates from the air. This rating measures cleaned air by CFM (cubic feet per minute), with separate CADR scores for different-size particles like pollen, tobacco smoke, and dust:

Smoke CADR Scale: 0-400 (Particles between 0.9 and 1.0 Micrometres (μm))
Dust CADR Scale: 0-450 (Particles between 0.5 and 3 Micrometres (μm))
Pollen CADR Scale: 0-450 (Particles between 5 and 11 Micrometres (μm))

A good CADR rating should be at least two-thirds of a room’s floor area. If your room is 10 ft x 20 ft with a floor area of 200 sq ft, then an air purifier with a CADR of 150 or higher will work best in that room.

Sample Air Purifiers

Air Purifier CADR Exmples
Air Purifier	Smoke CADR	Dust CADR	Pollen CADR	Room Capacity
Air Purifier #1	157 CFM	173 CFM	185 CFM	Good for rooms up to 243 sq ft (i.e. living rooms and basements)
Air Purifier #2	70 CFM	101 CFM	130 CFM	Good for rooms up to 109 sq ft (i.e. bedrooms and other smaller rooms)

Other Ways to Increase Your Home’s Indoor Air Quality

Regularly use a vacuum with a HEPA filter and clean fabrics, carpets, bedding, and curtains.
Replace your HVAC air filter at least every 3 months and make sure to check the Minimum Efficiency Reporting Values (MERV) rating on your filter.
Make sure your space is getting enough ventilation. Weather permitting and if you don’t have a humidity problem, opening windows and doors can help along with using your exhaust fans in your bathrooms and kitchen.
Reduce your potentials sources of pollution by regularly grooming your pet to reduce airborne dander, using low-VOC cleaners and paints, and avoiding smoking indoors.

Understanding Your Dehumidifier & Air Purifier