Under Air Quality Monitoring and Feedback, which indoor pollutants are monitored?

• A. Particle Count (PM2.5, PM10); Ozone; Carbon Dioxide
• B. Ozone; Carbon Monoxide; Methane
• C. Carbon Monoxide; Nitrogen Dioxide; Radon
• D. Particulate Matter; Sulfur Dioxide; Ozone

Answer: (A)

Monitoring indoor air quality with real-time sensors focuses on pollutants that most directly reflect occupants’ exposure and the effectiveness of ventilation and filtration. Particulate matter, including PM2.5 and PM10, captures inhalable particles from indoor activities and outdoor air that can irritate the lungs and contribute to health issues. Ozone is a reactive gas that can enter from outdoor air or other sources and interact with indoor surfaces, so tracking it helps assess potential oxidative and irritant exposure indoors. Carbon dioxide serves as a practical proxy for ventilation effectiveness and occupancy load; rising CO2 levels typically indicate that outdoor air exchange isn’t keeping pace with use, signaling a need to increase ventilation or adjust filtration.

The other options include pollutants that are not the focus of this monitoring and feedback concept. Methane, carbon monoxide, radon, nitrogen dioxide, sulfur dioxide, and various VOCs may be relevant in other contexts, but the WELL Air Quality Monitoring and Feedback requirement centers on PM (PM2.5/PM10), ozone, and CO2 to provide meaningful, actionable feedback for typical indoor environments.