`` In the 40-plus years since the Clean Air Act was passed , L.A. has never been fully in compliance with EPA standards , even though it has continued to improve . '' NEW : Beijing recording ` ` hazardous '' levels of air pollution ' . NEW : Children in worst - affected areas ordered to stop outdoor sports activities . Reports of respiratory problems -- and sale of masks -- skyrocket . U.S. Embassy in Beijing reports an exposure of more than 700 micrograms daily .
NEW : Beijing recording ` ` hazardous '' levels of air pollution ' . NEW : Children in worst - affected areas ordered to stop outdoor sports activities . Reports of respiratory problems -- and sale of masks -- skyrocket . U.S. Embassy in Beijing reports an exposure of more than 700 micrograms daily .