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How to Buy an Air Purifier

Whether you suffer from allergies or just need to clear the air in a large space, an air purifier is a great addition to any home. This filtration machine can help reduce the amount of harmful particles and irritants that flow throughout the air. Before making a decision, it’s important to know what to look for in an air purifier for your home. Here are some helpful tips to consider.

Know Your Home’s Environment

Even if you’re a clean person, air pollution levels can accrue up to five times more indoors than they do outdoors, according to the Environmental Protection Agency (EPA). Certain factors can increase the number of irritants throughout your home, such as pet dander or tobacco. An air purifier can help clear out some of these harmful pollutants.

Determine the Right CADR for the Room

While an air purifier is portable, a room’s size can help or hinder the device’s effectiveness. Always make sure to check the Clean Air Delivery Rate (CADR) seals when buying an air filtration machine. CADR determines how much air a device can filter per minute based on a room’s cubic feet. These figures are determined by the Association of Home Appliance Manufacturers (AHAM) to give consumers easy comparison ratings.

The higher the ratings, the faster the device can filter air. Most machines list three separate ratings for smoke, dust and pollen, which are considered the riskiest types of airborne particles. Make sure to multiply each CADR score by 1.55 to determine which size room the machine works best in when filtering smoke, dust or pollen. For example, if a machine has a smoke CADR of 80, it should work well in a 124 sq. ft. room. The following are standard CADR ranges for the three major contaminants:

  • Smoke: 10-450 CADR
  • Dust: 10-400 CADR
  • Pollen: 25-450 CADR

Check out the Room’s Layout

The standard CADR ratings are based on rooms with 8 ft. ceilings. If a room’s ceiling is higher than 8 ft., select an air purifier with slightly higher CADR ratings. When placing a purifier in a space with an open floorplan, you should also choose a machine with higher CADR ratings. Another option is to place two devices at opposite ends of the room, so the air is cleaned effectively.

Consider an ENERGY STAR® Purifier

On average, an air purifier with ENERGY STAR® certification can be up to 40% more efficient than a standard model. This option not only can help cut down on the amount of energy you consume, but it also can help save you money. In fact, some states have special rebate programs for purchasing an ENERGY STAR® appliance.

Research Air Purifier Features

While not all options come with every convenience or add-on, make sure to find a machine that suits you best. Here are some of the most common air purifier features you’ll find on the latest models.

  • High-efficiency particulate air (HEPA) filter - A purifier with an HEPA filter is designed to capture a large amount of particles that are as small as 0.3 microns, helping eliminate allergens and other harmful pollutants from the air.
  • Pre-filter - Many of the latest models feature a charcoal pre-filter that withholds odor and cleans the air before reaching the main filter.
  • Indicator light - The indicator light informs you when the machine’s filter needs to be changed. Some models have a second light to indicate when the pre-filter is past its effective usage.
  • Timer - This function allows you to program when the purifier turns on or off, so you can set it to run any time of day.
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