How to Test Air Quality in Your Home | Simple Steps That Work

Testing home air quality starts with a radon test kit, working CO and smoke alarms, plus a continuous monitor for pollutants like PM2.5 and VOCs.

You don’t need a lab or an expert to know what’s in the air you breathe. The EPA’s guidance for a basic check comes down to three moves: run a radon test, confirm your carbon monoxide and smoke alarms work, and add an indoor air quality monitor if you want ongoing readouts of dust, gases, and humidity. Here’s how to test air quality in your home without wasting money on unnecessary gear.

What to Test First: Radon, CO, and Smoke

Radon is the pollutant experts care about most, because it’s a colorless, odorless gas linked to lung cancer. The U.S. Consumer Product Safety Commission (CPSC) recommends measuring radon in every home and notes that many low-cost DIY test kits are available.

For carbon monoxide and smoke, the answer isn’t a kit — it’s an alarm. The EPA states that all homes should have working CO and smoke alarms installed. Test them monthly and replace batteries on a schedule.

How to Run a Radon Test Properly

The EPA says to test radon on the lowest lived-in level of your home — the basement if someone spends time there, otherwise the first floor. Retest after any remodeling if that level wasn’t tested before, such as when a basement is finished for the first time.

When buying a DIY kit, the CPSC advises choosing one that has passed the EPA’s testing program or is state-certified. Look for “Meets EPA Requirements” on the packaging.

Using an Indoor Air Quality Monitor

An IAQ monitor gives you continuous, real-time data instead of a one-time snapshot. Consumer guidance suggests choosing a monitor for the pollutants that concern you, placing it in the room where pollution is suspected, then reviewing the data for patterns before taking action.

Common sensors measure PM1, PM2.5, and PM10 (particulate matter), CO2, VOCs, temperature, and humidity. Higher-end models add radon, carbon monoxide, nitrogen oxides, or formaldehyde.

Try these placement strategies:

• Basement or bathroom when you suspect mold or moisture issues
• Bedrooms and living rooms where your family spends the most time
• The room where you notice odors, dust, or stuffiness

Remember that software updates matter, and some professional devices need periodic calibration. Follow the manufacturer’s instructions to keep readings accurate.

Prices and availability shift, so check current listings before buying. App and smart-home compatibility also varies by model, so verify what works with your setup. If you’re ready to compare tested options side by side, our roundup of the best home air quality tests walks through the top picks.

When to Fix vs. When to Just Monitor

Don’t rely on your nose to detect dangerous indoor air problems. The CPSC warns that radon cannot be smelled, and CO requires dedicated alarms, not your senses. A monitor is a diagnostic tool, not a solution — use the data to guide action.

The EPA’s core advice for improving air quality remains: control pollution sources at their origin, increase ventilation, and use supplemental air cleaning or filtration where needed. Monitoring tells you which of those steps matters most in your home.