Air pollution refers to the production and living activities of human beings to make a certain substance into the atmosphere, so that the chemical, physical, biological and other aspects of the characteristics of the atmosphere to change, affecting people’s lives, work, endangering human health, affecting or endangering the survival of a variety of organisms, directly or indirectly damage to the phenomenon of equipment, buildings and so on. Air pollutants are: soot, total suspended particulate matter, respirable suspended particulate matter (floating dust), nitrogen dioxide, sulfur dioxide, carbon monoxide, ozone, volatile organic compounds and so on. Many studies have confirmed that air pollutants are important triggers of pediatric asthma. How to know the daily air quality condition? You can install the cell phone app that broadcasts the air quality, and children can arrange their daily life and take corresponding countermeasures according to the index: 1, air quality is good: the index is 0 to 100. normal activities. 2, air quality is mildly polluted: the index is 0 to 100. 2.Mildly polluted air quality: the index is 100-200, asthmatic children should reduce physical exertion and outdoor activities. 3.Moderate air quality pollution: the index is 200～300. children with asthma should stay indoors and reduce physical activity. 4. Heavily polluted air quality: index >300. Asthmatic children should stay indoors and avoid physical exertion, and healthy people should avoid outdoor activities.