The air quality can't be better than that of physical education class.

You can't go to physical education class if the air quality index reaches more than 200.

When the early warning response level of heavily polluted weather reaches the blue warning, that is, when the regional air quality index (AQI) reaches above 200, the early warning level IV will be started, and outdoor activities such as physical education class will be stopped in primary and secondary schools and kindergartens. Patients with heart disease and lung disease and students with special physique should stay indoors.

When the early warning response level of heavily polluted weather reaches orange warning, that is, when the regional air quality index reaches above 400, the early warning level II will be started, schools and kindergartens will stop all outdoor activities and outdoor sports competitions, and outdoor collective activities such as sports examinations organized by schools, counties and cities will be postponed, and necessary protective measures will be taken at the same time.

Air quality index:

At present, the air pollution index (API) adopted in China is divided into five grades, and the API value is less than or equal to 50, which means that the air quality is excellent, which is equivalent to reaching the first-class national air quality standard and meeting the air quality requirements of areas requiring special protection such as nature reserves and scenic spots. The API value is greater than 50 and less than or equal to 100, which means that the air quality is good, which is equivalent to reaching the second-class national air quality standard.

The API value is greater than 100 and less than or equal to 200, indicating that the air quality is slightly polluted, which is equivalent to reaching the national air quality third-class standard; After long-term contact, the symptoms of susceptible people are slightly aggravated, and healthy people have irritating symptoms. The API value is greater than 200, indicating that the air quality is poor, which exceeds the national air quality level 3 standard and is harmful to human body after exposure for a certain period of time.