How to Compare HEPA Air Purifiers

If you have allergies or asthma, a high efficiency particulate air purifier, also called a HEPA purifier, will help make your home's air cleaner and less irritating to your respiratory system. According to Achoo Allergy & Air Products, an air purifier must filter at least 99.7 percent of all particles 0.3 microns or larger to be considered a HEPA system. This means that for the average consumer, a HEPA purifier filters most dust, pollen, mold and dander from the air. Unfortunately, a HEPA purifier is effective only if you buy the right one for your individual needs, so it's important to shop and compare properly.

Instructions

• 1

  Compare the cubic feet per minute (CFM) rating between HEPA purifiers. A larger space will require a higher CFM rating to properly filter all of the air. If you purchase a HEPA filter with a CFM that is too low for the room, the filter won't work right. Conversely, a CFM rating that is too high will consume unneeded energy and raise your electricity bill. Generally speaking, a CFM rating of 200 will adequately filter a room with about 250 sq. ft. of floor space.

• 2

  Consider 360-degree intake models if you need omni-directional purification for a large space. However, if you are purifying air in a small room where you can easily point a small unit toward the center, a uni-directional model will work just fine and cost a little bit less than a 360-degree model.

• 3

  Compare warranties as you shop for your new purifier. Many HEPA purifiers offer three- to five-year warranties; others have limited one- to two-year warranties. Unless you're willing to roll the dice, a model with a three- to five-year guarantee is ideal. You may pay a little extra for such a model, but you'll be ensured a quality product.

• 4

  Look for mobility options. Purifying every room in your house can be very expensive, and many consumers move their purifiers around during the day to filter air in whatever room they happen to be in at the time. Home-based HEPA purifiers range in weight from a few pounds to up to 40 or 50 pounds. Weight is often overlooked when comparing models, but it's important to consider if you'll be moving the unit a lot. Some models have wheels for easier mobility.

• 5

  Test the machine's noise levels if possible. While you may not be able to take products out of the box and plug them in prior to purchasing, it doesn't hurt to at least ask a sales associate if this is possible. Most HEPA purifiers will be advertised as "whisper quiet," but this phrase is relative and doesn't mean much. The best way to judge the noise level of a purifier is to simply plug it in and listen to it run.