|AirNow Home||>>||California||>>||Redwood City|
AQI: Good (0 - 50)
Air quality is considered satisfactory, and air pollution poses little or no risk.
AQI: Moderate (51 - 100)
Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
AQI: Unhealthy for Sensitive Groups (101 - 150)
Although general public is not likely to be affected at this AQI range, people with lung disease, older adults and children are at a greater risk from exposure to ozone, whereas persons with heart and lung disease, older adults and children are at greater risk from the presence of particles in the air.
AQI: Unhealthy (151 - 200)
Everyone may begin to experience health effects; members of sensitive groups may experience more serious health effects.
AQI: Hazardous (301 - 500)Action Day
Health warnings of emergency conditions. The entire population is more likely to be affected.