How to measure the air quality in your home by yourself and with a pro

According to the U.S. Environmental Protection Agency, indoor air can be three to five times more polluted than outdoor air, and most people spend 90 percent of their time indoors. Testing your indoor air quality is essential to ensure a healthy living environment. To provide you with expert advice on how to measure and improve air quality in your home, we consulted with a team of experts at PopSci.

Michael Rubino, a mold and air-quality expert, emphasizes the importance of indoor air quality on our overall health. He explains that a variety of contaminants can negatively impact our health, including VOCs, mold, bacteria, allergens, pesticides, and more.

Modern construction practices and the push for energy efficiency have contributed to lower indoor air quality by creating tightly sealed buildings with limited airflow. This, combined with manmade contaminants, can create a hazardous environment filled with substances like Benzene, Xylene, and Mycotoxins.

To assess your indoor air quality, Brad Roberson suggests checking for common warning signs like musty odors, dust buildup near vents, and physical symptoms like sneezing and coughing. Maintaining humidity levels between 30 and 50 percent is also crucial for a healthy indoor environment.

For specific contaminant testing, Lisa Sternfeld recommends using affordable home test kits for allergens, mold, and volatile organic compounds (VOCs). These kits can help identify and mitigate common pollutants in your living space.

She suggests that VOC testing kits can assist in identifying high concentrations of VOCs in your indoor air.

Simple air-quality monitors

For a broader monitoring approach, Sternfeld suggests using handheld or portable air-quality monitors. These monitors can detect particulate matter (PM2.5) like pollen and smoke particles from cooking, carbon dioxide (CO2), and VOCs, which are commonly found in paint, furniture, and cleaning products.

Temtop M2000 2nd Generation

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Additionally, these devices offer real-time data, enabling adjustments to airflow or filtration as needed.

Smart air purifiers, such as those featured in our list of the best air purifiers for asthma, come equipped with real-time monitoring capabilities.

Levoit EverestAir Smart Air Purifier

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The Levoit EverestAir Smart Air Purifier can monitor and capture various contaminants, including dust, pollen, and other allergens. Its auto feature detects air-quality levels and adjusts settings accordingly, with indicator rings changing colors to signify good, fair, or poor air quality.

Roberson concurs, stating that consumer-level indoor air-quality monitors can track VOC levels from sources such as cleaners, paint, or furniture. They can also monitor CO2 levels, temperature, and humidity. However, he notes that while these monitors provide a helpful overview, they are not as precise or detailed as professional equipment.

Airthings 360 View Plus Air-Quality Monitor

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The Airthings 360 View Plus Air-Quality Monitor can monitor radon, VOCs, particulate matter, CO2, humidity, temperature, and more. This wireless monitor can be wall-mounted or placed on a table, and the accompanying app allows you to view real-time data remotely.

How a professional tests your indoor air quality

Rubino provides bulleted lists outlining what professionals test for and the tools they use, comparing them to those available directly to consumers.

What professionals test for

• Particulate Matter (PM1, PM2.5, PM10) – fine particles that can affect lungs
• Volatile Organic Compounds (VOCs) – off-gassed chemicals from furniture, cleaners, etc.
• Formaldehyde – a common VOC from building materials
• Mold Spores and Mycotoxins – biological contaminants that impact immune system health
• Carbon Monoxide (CO) & Carbon Dioxide (CO₂) – for combustion safety and ventilation
• Humidity & Temperature – for mold and bacteria prevention
• Radon Gas – especially in basements and ground-level homes
• Bacteria & Actinobacteria – microbial contamination from water damage
• Airborne allergens – pollen, pet dander, and dust mites

What professionals use

• Laser Particle Counters – for measuring PM levels in real time
• VOC Detectors – using photoionization detection (PID) or flame ionization detection (FID)
• Formaldehyde Detectors – calibrated to industry standards
• Petri dish (agar), Surface Sampling, Air Sampling, and The Dust Test – analyzed in a lab for mold
• Thermal Imaging Cameras – to identify hidden moisture problems
• Borescopes & Moisture Meters – for inspecting inside walls and under floors
• Radon Test Kits (Continuous Monitors or Alpha Track) – for long-term exposure
• CO/CO₂ Monitors – to assess combustion safety and air exchange
• Lab Analysis – many samples are sent to accredited labs (e.g., for mold, mycotoxins, VOCs)

How that is different from DIY

Rubino explains that a professional indoor air quality (IAQ) assessment provides a more thorough, science-backed analysis of contaminants in your home, often involving lab testing and personalized recommendations. This approach is ideal for individuals experiencing health issues or recent events like water damage that could lead to increased contaminants.

In contrast, a homeowner assessment focuses on monitoring trends and maintaining general air quality, lacking the precision to identify specific sources. This serves as a preliminary step to determine if there is a problem before seeking professional assistance for a detailed evaluation.

According to Roberson, IAQ professionals, including HVAC experts, can assess and enhance indoor air quality using professional-grade equipment. HVAC inspections can identify airflow and cleanliness issues, with recommendations for solutions like electronic air cleaners, UV-C light purifiers, and activated carbon filters to improve air quality.