A man takes students leaving their school which was closed down due to heavy air pollution in Lahore, eastern Pakistan, on Nov. 15, 2019. The air quality in Lahore and adjoining districts on Friday surpassed a hazardous level, forcing local government to close down all public and private schools for two days, according to a notification issued by the Punjab School Education Department. (Photo by Sajjad/Xinhua)

A man is ready to take students to leave their school which was closed down due to the heavy air pollution in Lahore, eastern Pakistan, on Nov. 15, 2019. The air quality in Lahore and adjoining districts on Friday surpassed a hazardous level, forcing local government to close down all public and private schools for two days, according to a notification issued by the Punjab School Education Department. (Photo by Sajjad/Xinhua)

A man with his face covered rides a motorbike amid heavy smog in Lahore, eastern Pakistan, on Nov. 15, 2019. The air quality in Lahore and adjoining districts on Friday surpassed a hazardous level, forcing local government to close down all public and private schools for two days, according to a notification issued by the Punjab School Education Department. (Photo by Sajjad/Xinhua)

Passengers wait at a railway station amid heavy smog in Lahore, eastern Pakistan, on Nov. 15, 2019. The air quality in Lahore and adjoining districts on Friday surpassed a hazardous level, forcing local government to close down all public and private schools for two days, according to a notification issued by the Punjab School Education Department. (Photo by Sajjad/Xinhua)

Commuters are seen amid heavy smog in Lahore, eastern Pakistan, on Nov. 15, 2019. The air quality in Lahore and adjoining districts on Friday surpassed a hazardous level, forcing local government to close down all public and private schools for two days, according to a notification issued by the Punjab School Education Department. (Photo by Sajjad/Xinhua)