• Delhi's Air Quality Index hit a severe level of 491 on Sunday.
• The Commission for Air Quality Management enforced Stage IV measures to combat pollution.
• Residents, especially vulnerable groups, are advised to stay indoors.
• Authorities suspended construction activities and restricted older diesel vehicles.
• Experts emphasize the need for urgent action to reduce emissions.

Delhi and surrounding regions are engulfed in hazardous smog, with the Air Quality Index (AQI) reaching a distressing score of 491 as of Sunday morning. This alarming figure categorizes the city's air quality as "severe plus," significantly affecting visibility and overall public health. All 40 monitoring stations in the area recorded "severe" levels of pollution, necessitating immediate action from authorities, according to Indiatimes, Reuters, and AA.

In response to the deteriorating air quality, the Commission for Air Quality Management (CAQM) invoked Stage IV of the Graded Response Action Plan, which includes suspending all construction activities and restricting the entry of older diesel trucks into the city. The authorities have also mandated hybrid schooling, with implications for both public and private institutions to operate at half capacity, as detailed by Reuters and The Jakarta Post.

Officials have advised residents, particularly children, the elderly, and those with pre-existing health conditions, to minimize outdoor activities and remain indoors. When going outside is unavoidable, wearing masks is strongly encouraged to mitigate health risks associated with air pollution. The sharp increase in pollution levels has been attributed to factors such as high humidity and unfavorable wind conditions that prevent the dispersal of pollutants, according to Indiatimes and AA.