When shopping for an air purifier, it’s important to consider several factors to ensure you get the most effective one for your needs. Here are some of the key features to look for:

1. HEPA Filters

One of the most important features to look for in an air purifier is a HEPA (High-Efficiency Particulate Air) filter. HEPA filters are designed to capture 99.97% of particles as small as 0.3 microns, including allergens like pollen, pet dander, and dust mites. This makes them highly effective for allergy relief.

When purchasing an air purifier, make sure it uses a True HEPA filter, not just a “HEPA-type” filter. True HEPA filters meet specific industry standards, while HEPA-type filters may not be as efficient at capturing smaller particles.

2. Activated Carbon Filters

In addition to HEPA filters, some air purifiers also feature activated carbon filters. These filters are especially helpful for removing odors and gases, such as smoke, cooking smells, or volatile organic compounds (VOCs) from paints and cleaning products. While carbon filters aren’t necessary for everyone, they can be beneficial if you’re sensitive to odors or live in an area with high pollution levels.

3. Room Size Coverage

Before buying an air purifier, you’ll want to consider the size of the room where you’ll be using it. Air purifiers are rated based on the square footage they can effectively clean. Look for a model that is designed to handle the size of the room you intend to use it in.

For example, if you’re using the purifier in a small bedroom, a compact unit with coverage of around 150 to 300 square feet might be sufficient. For larger areas, such as living rooms or open-plan spaces, you’ll need a more powerful air purifier that can handle 500 square feet or more.

4. Air Changes per Hour (ACH) Rate

The ACH rate tells you how many times the air purifier can clean the air in a room in one hour. For allergy sufferers, it’s recommended to look for an air purifier with an ACH rate of at least four air changes per hour. This means the purifier will clean the entire room’s air at least four times in an hour, ensuring allergens are continuously being removed.

5. Noise Level

Air purifiers use fans to pull air through their filters, so it’s important to consider the noise level of the unit, especially if you plan to use it in a bedroom or a quiet space. Most manufacturers list the noise level in decibels (dB). Look for a model that operates at a noise level of around 30-50 dB on its lowest setting, which is comparable to a soft conversation or the hum of a refrigerator.

6. Energy Efficiency

Since air purifiers often run continuously, it’s worth considering the energy consumption of the unit. Look for models with an Energy Star rating, which means they meet energy efficiency guidelines set by the U.S. Environmental Protection Agency (EPA). Energy-efficient models will help you save on electricity bills in the long run.

7. Maintenance and Filter Replacement Costs

Air purifiers require regular filter replacements to maintain their effectiveness. HEPA filters typically last around 6 to 12 months, while activated carbon filters may need to be replaced every 3 to 6 months. Before buying, check the cost of replacement filters and factor that into your decision. Some units also have indicator lights that let you know when it’s time to change the filters, making maintenance easier.