Air Quality Index Descriptions
AQI for San Dimas and Surrounding Areas  Enter "Horsethief Canyon Park San Dimas, CA" in address search box & click Search Maps   Information on how horses are affected by smoke Info from Horse.com
The purpose of the AQI (Air Quality Index) is to help you understand what local air quality means to your health. To make it easier to understand, the AQI is divided into six categories Each category corresponds to a different level of health concern. The six levels of health concern.
Level Of Health Concern	Description
Good	The AQI value for your community is between 0 and 50. Air quality is considered satisfactory, and air pollution poses little or no risk.
Moderate	The AQI for your community is between 51 and 100. Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people. For example, people who are unusually sensitive to ozone may experience respiratory symptoms.
Unhealthy for Sensitive Group	When AQI values are between 101 and 150, members of sensitive groups may experience health effects. This means they are likely to be affected at lower levels than the general public. For example, people with lung disease are at greater risk from exposure to ozone, while people with either lung disease or heart disease are at greater risk from exposure to particle pollution. The general public is not likely to be affected when the AQI is in this range.
Unhealthy	Everyone may begin to experience health effects when AQI values are between 151 and 200. Members of sensitive groups may experience more serious health effects.
Very Unhealthy	Values between 201 and 300 trigger a health alert, meaning everyone may experience serious health effects.
Hazardous	Values over 300 trigger health warnings of emergency conditions. The entire population is more likely to be affected.