A common second question after "is my air bad?" is "how does my home compare?" The dashboard answers both. Population-level studies provide the distribution; your sensor data places you on it. The most-cited population study is Klepeis et al. (NHAPS), which characterized how Americans actually spend their time indoors; LBNL's Indoor Air Quality science portal compiles updated home-air-quality distributions.
A typical North American single-family home with average occupancy reads in roughly the following bands when averaged over a month: CO2 600 to 1,100 ppm, PM2.5 5 to 15 µg/m³, VOC index 80 to 150, RH 30 to 55%, temperature 19 to 23 °C. Apartments tend to run higher on CO2 and humidity (denser occupancy, smaller air volumes, less envelope leakage) and lower on PM (less outdoor infiltration through smaller window-to-wall ratios).
Your placement on the distribution matters less than the trend over time. A home in the 75th percentile for PM2.5 that is steadily improving (because you installed HEPA, fixed a flue, or got a new range hood) is going in the right direction. A home in the 30th percentile that is drifting upward (a humidifier set too high, a slow basement leak, a new piece of off-gassing furniture) is worth investigating. The dashboard shows both the absolute position and the trajectory.
Benchmarking is most useful when paired with a goal: WHO 2021 PM2.5 annual (5 µg/m³) is a target. ASHRAE 62.1 CO2 equivalent (1,100 ppm peak in occupied rooms) is a target. 30 to 50% RH (see humidity) is a target. The dashboard shows percent-of-time-in-band for each, which is the practical way to track progress toward those targets.
References
- Klepeis et al. - National Human Activity Pattern Survey doi.org
- EPA - Improving indoor air quality www.epa.gov
- WHO Global Air Quality Guidelines (2021) www.who.int
- LBNL Indoor Air Quality science portal iaqscience.lbl.gov
