How we research and choose

Sources

Every guide lists its sources at the end of the page. They come from:

• Makers' product pages, spec sheets and manuals (Levoit, Coway, Winix, Blueair, Honeywell, Dyson, IQAir, Airthings, Frigidaire, Midea and others)
• Certification databases: AHAM Verifide (CADR), the California Air Resources Board's certified air cleaner list, ENERGY STAR
• US EPA, CDC, WHO and state health agency guidance on particles, ozone, radon, CO2, humidity and mold
• ASHRAE standards (52.2 for MERV, 62.2 and 241 for ventilation and clean air) and peer-reviewed sensor studies
• Our own arithmetic (CADR per room, air changes per hour, filter cost per year, dehumidifier sizing), shown on the page

When makers state the same kind of figure in different ways (a peak rating against a continuous one, a nominal value against a measured one, a claimed maximum against a typical result), the guide says which one it is quoting. When a maker does not publish a figure, the guide says so rather than estimating it.

How a product earns a pick

1. We list what is actually for sale to US buyers on the day of writing, checking each listing on Amazon US through Amazon's product data service, or the maker's own store for brands that sell only direct.
2. We read the maker's own specifications and manual for each one and put the figures that matter side by side.
3. We weigh those figures against the job: what the product is for and who will use it, the warranty, what is included, and what owners report going wrong.
4. We name a pick for each kind of buyer and say who should skip it.

Commission does not decide the order. Amazon is the only retailer we earn from. A product sold only by its maker is linked to the maker's store, which pays us nothing, and it is picked or skipped on the same terms as the rest. No brand pays for a place in a guide.

How the guides are written

Guides are researched and drafted with the help of AI tools and checked against the sources they cite. We do not publish invented test results or first-hand claims we cannot back up.

Prices

Retailer prices change daily, so guides do not print them. Where cost matters (a budget pick, the yearly cost of filters), the guide quotes the maker's own list price and links to it. The retailer's page has the current price.

Keeping pages current

When a product is discontinued, a listing disappears or a spec changes, the page is updated and its updated date changes. Corrections from readers go to info@indoorairreview.com.