Air Purifiers 101

Why Purify Your Indoor Air?

Indoor air may be up to 5 times more polluted than outdoor air.

According to the EPA, Americans spend up to 90 percent of their time indoors. Children and the elderly are especially sensitive to air pollution. Most pollutants are microscopic and can easily pass through the nose or throat directly into the lungs.

Common indoor air pollutants include:
  • Mold**
  • Dust mites in pillows, blankets or stuffed animals
  • Tobacco smoke & cooking fumes
  • Pet Hair and dander
  • Pollen and dust
The good news is ... you can help protect yourself and your family from indoor air pollution.

Holmes® and aer1® disposable filters trap and lock up to 99.97% of dust and other harmful airborne allergens before they settle in your home.*(2) Breathe cleaner, fresher indoor air.

To learn more about the aer1® system, click here

**EPA Establishment #071027-MEX-001

How Does an Air Purifier Work ?

Air purifiers are designed to help remove airborne particles and odors from air passing through the filter.

  1. Using fans, dirty air is brought in through an intake grill typically found on the front or back of the unit.
  2. The air then passes through filters helping to remove pollutants, allergens and other contaminants from the air you breathe. Information on specific filters can be found below. 
  3. After the air is filtered, a powerful fan quietly distributes the clean air back into the room. As an added function, some air purifiers include Ionizers that release negatively charged ions, which attach to dander, pollen and other small, positively charged impurities to form larger particles that are more easily trapped by the filter. 

How is the Performance of an Air Purifier Measured?

Most air purifiers are tested for efficiency in terms of Clean Air Delivery Rate (CADR).

What it is: CADR is a third party test measure indicating the volume of filtered air delivered by an air purifier. The higher the CADR numbers, the faster the unit filters the air passing through the filter.

Why it is important: CADR is an objective way for you to compare the performance of one air purifier to another.

Tip: CADR values will vary by size of the product. The below information will assist you in purchasing a product with enough cleaning power by room size.

  • Small Room (nursery, office or small bedroom) – up to 155 sq ft Recommended CADR: up to 97
  • Medium Room (bedroom or family room) – up to 300 sq ft Recommended CADR: 98-130
  • Large Room (great rooms or large living spaces) – up to 500 sq ft Recommended CADR: 130 and up

Filtration Types

Holmes® and aer1® filters are specifically engineered to solve unique needs. Having the right filter to solve your particular issue, makes all the difference. See below for information on each filtration type based on your specific need.

For Allergy Symptoms

  • True HEPA Performance Plus Replacement Filter removes 99.99% of airborne particles as small as 0.3 microns
    • Bionaire Filter Comparizon
      • Most efficient Holmes filter technology
      • Helps eliminate allergens and pollutants such as pollens, pet dander, dust
      • No filter cleaning required
  • True HEPA Replacement Filter removes 99.97% of airborne particles as small as 0.3 microns
    • Bionaire Filter Comparizon
      • Higher cleaning air power than HEPA-type filters
      • Helps eliminate allergens and pollutants such as pollens, pet dander, dust
      • No filter cleaning required 

For Maintaining Wellness

  • HEPA Type Replacement Filter removes 99% of airborne particles as small as 0.2 microns
    • Bionaire Filter Comparizon
      • Effectively eliminates dust and air pollutants
      • Helps eliminates odors
      • Trap and toss for no loss of filter performance
  • HEPA Type Permanent Filter removes 99% of airborne particles as small as 0.2 microns
    • Bionaire Filter Comparizon
      • Captures dust and air pollutants
      • Required regular maintenance
  • Odor Eliminator Permanent Filter is infused with ARM & HAMMERTM Baking Soda for 10x more Odor Fighting Power
    • Bionaire Filter Comparizon
      • Ideal for eliminating odors from pets, tobacco smoke, cooking fumes and other unpleasant household odors

Tip: To learn more about the benefits of replacement vs. permanent filters,click here

What is a Micron?

Common airborne allergens range from 3-100x larger than 0.3 microns. Holmes True HEPA removes microns as small as 0.3 microns while HEPA Type removes microns as small as 2 microns.*

  • 0.3 microns
  • 1.0 Micron - Tobacco Smoke
  • 5.0 Microns - Cat Allergen
  • 10.0 Microns - Household Dust (Visible to the human eye)
  • 30 Microns - Pollen and Mold Spores
  • 100 Microns - Human Hair

*from air passing through the filter

How to Choose the Right Air Purifier

Choosing the right air purifier can be confusing and intimidating. The below will walk you through the correct steps to purchase the best product to solve your issue.

1. Select Room Size

SMALL ROOM up to 155 sq.ft

  • Ideal for small rooms and nurseries
  • Recommended Product Size: Desktop or Mini Tower

MEDIUM ROOM up to 300 sq ft.

  • Ideal for bedrooms and family rooms
  • Recommended Product Size: Tower

LARGE ROOM up to 500 sq.ft

  • Ideal for great rooms and larger living spaces
  • Recommended Product Size: Tower and Consoles

2. What's Your Problem


  • Allergen Removal Look for True HEPA Filtration 
    • Removes: Ragweed Pollen, Grass Pollen, Household Dust, Mold Spores, Pet Dander and Odor, Smoke, Dust Mite Debris, Tree Pollen
  • Dust Removal, General Use Look for HEPA type Filtration Electrostatic / Collector Plates
    • Removes: Pet Dander and Odor, Smoke, Household Dust
  • Odor Elimination Look for HEPA Type with Carbon Odor Elimination Pre-Filters
    • Removes: Pet Dander and Oder and Smoke
  • Germ Reduction Look for Ultraviolet (UV) Technology
    • Removes: Mold Spores and Dust Mite Debris

3. Select the Highest Clean Air Delivery Rate (CADR)

The Clean Air Delivery Rate (CADR) is a third-party testing measure that determines an air filter’s effectiveness in reducing airborne pollutants.

Tip: Look for tested products and only purchase from a reliable source. Holmes® is a leading brand in indoor air products delivering quality, value and peace of mind to you and your family.

Care and Cleaning  

  • Always unplug the air cleaner before moving or cleaning the unit, opening the grill, or changing the filters. It should also be unplugged whenever the unit is not in use. To disconnect the unit, be sure to pull the plug and not the cord.
  • Permanent filters can be vacuumed every few months for easy cleaning.
  • The washable pre-filter captures larger particles and extends the permanent filter’s cleaning cycle.
  • NEVER drop or insert any objects into the openings of the unit.
  • Do not operate any appliance with a damaged cord or plug.
  • DO NOT place anything on top of unit.
  • NEVER use detergents, gasoline, glass cleaner, furniture polish, paint thinner, or other household solvents to clean any part of the appliance.
  • Always turn the appliance off before unplugging it.
  • The ionizer may cause a static charge to build up on the air outlet grill. A static charge may be felt if the unit is not properly grounded. To avoid a static charge, plug the unit's three-prong plug into a grounded outlet, or properly install a ground adaptor. The static charge will not occur if the ionizer is off.
  • This appliance should only be used in rooms with temperatures between 4° C (40° F) and 43° C (110° F).

Cleaning and maintenance:

  • Turn off and unplug the unit before cleaning.
  • The outside of the air purifier can be cleaned with a soft, damp cloth.
  • The filtered air outlet/top air vent can be cleaned of dust with a small, soft brush.
  • You can remove the air inlet/front grill for cleaning by opening the air cleaner’s door. Carefully place fingers in the indentation on the right side of the door and gently pull forward. Once the door is open to 90 degrees, pull the grill up and forward. Once removed, the front grill can be cleaned with warm, soapy water. Do not place in dishwasher. Make sure the grill is completely dry before reinstalling.
  • If you wish to clean the inside of the air purifier, please remove filters and only use a dry, soft cloth to wipe it down.
  • DO NOT wash HEPA or CARBON filters.
  • WARNING: Do not allow moisture to come in contact with the main housing of the air cleaner.

Pre-filter cleaning instructions:

  • Turn off and unplug the unit before cleaning.
  • Every 2-3 weeks check the conditions of the washable foam pre-filter.
  • Open the front door and remove the pre-filter frame to examine the pre-filter.
  • If the pre-filter has a noticeable amount of dust, lint or particulate accumulation, wash it by hand in warm soapy water. The pre-filter must be washed at least every 30 days, or more often as necessary. If the pre-filter is worn or damaged replace it. DO NOT wash in an automatic washer. Gently hand wash only.
  • After washing, rinse and dry the pre-filter thoroughly before replacing it into the air cleaner door. DO NOT dry the pre-filter in an automatic dryer. Dry only by dabbing gently with a dry, cloth hand towel.
  • Replace pre-filter in door and latch pre-filter frame.

Cleaning a permanent filter:

  • The a permanent filter is designed to never need replacement. However, we recommend regular cleaning for optimal performance.
  • Every few weeks, check the condition of the filter.
  • After approximately 3 months of operation, a Filter Clean Indicator will alert you to clean the filter before further use.
  • To clean the filter:
    • Turn off and unplug the air cleaner.
    • Remove the air inlet grill by pulling on the tab.
    • Remove and examine the foam pre-filter.
    • If it has collected dust or lint, remove and wash it in warm, soapy water. Rinse and drip dry thoroughly before placing it back into the grill inlet.
    • Check the condition of the a permanent filters and remove if dirty.
    • Clean the a permanent filter.
    • Using your vacuum cleaner, run the brush attachment along both sides of the filter and clean between the pleated layers. IMPORTANT: Do not use water, household cleaners, or detergents to clean the a permanent filter.
  • The filter may appear discolored, even after vacuuming. This is normal and does not affect performance in any way—a new filter is not necessary.