• What is the AQI?

  • The Air Quality Index (AQI) is the EPA's system for reporting air quality, focusing on five major pollutants: ground-level ozone, particle pollution (PM2.5 and PM10), carbon monoxide, sulfur dioxide, and nitrogen dioxide.
  • The scale ranges from 0 to 500, with higher numbers indicating worse air quality.
  • It is divided into six color-coded categories (Green, Yellow, Orange, Red, Purple, Maroon) to help the public quickly understand health risks.

• Evolving Standards

  • The EPA is required by the Clean Air Act to review national air quality standards every five years.
  • Standards have become more stringent over time; for instance, what was considered "good" air quality 10-25 years ago might not meet today's stricter standards.

• International Variations

  • AQI systems vary globally. Examples include Canada's Air Quality Health Index (AQHI), China's Individual Air Quality Index (IAQI), and Europe's Common Air Quality Index (CAQI).

• Limitations of the AQI

  • Distance of Monitors: AQI readings are based on about 5,000 monitors across the U.S. These can be located miles away from an individual's home (e.g., 10+ miles), meaning they may not reflect the actual air quality at a specific residence.
  • Local Pollution Sources: The general AQI does not account for immediate, hyper-local pollution sources, such as a neighbor burning leaves or a truck idling nearby.

• Indoor Air Quality Myth

  • While Americans spend about 93% of their time indoors or in vehicles, they are not escaping outdoor pollution.
  • Outdoor air penetrates indoor environments. Because people spend so much time inside, the majority of their exposure to outdoor air pollution actually occurs indoors.

Now all that is needed is the Darth Vader black cape!

Example Air Quality project with pi and complete code. Three sensors connected: particulate, temperature, and humidity. Includes link to complete project and graphs displayed on builtin webserver.