human
I've heard that the air quality in my area is bad. How can I tell if it's safe to go outside?
assistant
You should check the Air Quality Index (AQI) before going outside. The AQI measures the level of air pollution, and provides a rating for how clean or polluted the air is. Generally speaking, when the AQI is below 100, you are advised to limit your outdoor activities. If the AQI is above 200, you should avoid strenuous physical activity outdoors.