On January 11 and 17, PM2.5 and PM10 levels in Delhi exceeded WHO guidelines. Therefore, even if pollution levels were reduced to 0.1 micrograms per cubic meter from those dates onward, Delhi would still fail to meet the annual WHO guidelines, said a study by the Centre for Research on Energy and Clean Air (CREA). Similarly, Delhi surpassed national standards for PM2.5 and PM10 on May 7 and April 2, respectively.
