Buying an Air Purifier

Today’s energy-efficient technology makes homes air tight, holding warm air inside during the winter and cool air inside during the summer. Unfortunately, the home isn’t allowed to breathe and opening a window isn’t always an option. Air purifiers are designed to reduce allergens in the home and are good for allergy and asthma sufferers.

Where do all the air pollutants and allergens in my home come from?

Air pollution, in general, is a top environmental concern in the world today. Indoor air pollution is part of that concern. Indoor air pollution levels can be up to five times higher than pollution levels outside.

Indoor air pollution commonly consists of the following allergens and pollutants:

  • Second-hand tobacco smoke is one of the smallest allergen particles and is linked to many health problems including asthma.

  • Animal dander is created from dander flakes shed by pets. It can cause asthmatic and allergic reactions in people who are allergic to cats and dogs. Sometimes removing the pet from the home isn’t enough. Dander usually remains in the home long after the pet has left.

  • Pollen is created by trees, flowers and grass. Each time a door or window is opened, millions of pollen particles enter the home. Most allergy sufferers are allergic to one or more types of pollen.

  • Mold and mildew can be found where there is a supply of water or where it is warm and humid. The shower, kitchen and basement are perfect places for these plant spores to grow.

What type of air purifier do I need?

The most important thing to look for when you buy an air purifier is the correct size for your room. Air purifiers are portable and can be moved from one room to another, provided the rooms are similar in size.

What size do I need?

The first thing you need to know when purchasing an air purifier is what CADR means. The Clean Air Delivery Rate (CADR) seal program was developed by the Association of Home Appliance Manufacturers (AHAM) to help consumers choose air purifiers. CADR is based on the cubic feet of air a purifier can filter per minute. The higher the CADR number the faster the unit cleans the room’s air. Purifiers with the CADR seal remove tobacco smoke particles, animal dander, mold, mildew, dust and pollen particles. Use the following formula to decide which CADR is correct for your room:

Square footage x .75 = CADR

Example: If your room is 16′×17′, which equals 272 sq. ft., you’ll need an air purifier that has a CADR of at least 204.

272 × .75 = 204

If an air purifier isn’t available with the exact CADR you calculate, round up. For instance, if your room size requires a CADR of 204, purchase one with a CADR of 220.

If you have a room with ceilings higher than 8’, move up to the next level CADR for a larger room. If you have an open floor plan, purchase two small units. The units can be moved to different areas in the room, cleaning the air more efficiently than one unit.

What else should I look for?

Different brands of air purifiers have different features. Here are some additional features to look for:

  • Air purifiers today commonly use the High Efficiency Particulate Arresting (HEPA) filter. HEPA filters remove 99.97% of air pollutants .3 microns or larger from the air. HEPA filters also remove tobacco smoke, household dust, mold spores, animal dander and pollen.

  • Frequency of filtering cycle (average every 10 minutes) can vary between models.

  • Check filter control is available on some models.

  • Speed controls for times when filtering needs vary.

  • Some air purifiers offer 360° air flow based on the shape of the model (cylindrical or rectangular).

Good idea: You know that houseplants enhance the beauty of your surroundings. Did you know that many actually clean pollutants out of the air?

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