Here are the main points in this big story:
Delhi's 24-hour average air quality index stood at 399 on Friday. An AQI between 201 and 300 is considered 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.
Centre's air quality panel on Friday noted that the AQI is likely to slip into the 'severe' category due to calm winds and stable atmospheric conditions.
The air quality is likely to remain 'severe' till tomorrow.
The next stage - 'Severe Plus' - includes steps like a ban on the entry of trucks into Delhi, closure of educational institutions and the plying of vehicles on an odd-even basis, etc.
The Delhi government will decide today whether a ban should be imposed on using BS-III petrol and BS-IV diesel four-wheelers.
Non-polluting activities such as plumbing, carpentry, interior decoration, and electrical work are allowed.
Earlier, the Centre's air quality panel on Wednesday said industries using unapproved fuels, including coal, in Delhi-NCR will be shut from January 1 and heavy fines will be imposed on them.
However, the use of low-sulphur coal in thermal power plants is allowed, it said.
Stubble burning, a major reason behind hazardous pollution levels in Delhi-NCR in October-November, reduced by 30 per cent in Punjab and 48 per cent in Haryana this year.
A government report showed that the pollutant load in the Yamuna has increased substantially over the last five years. The Delhi government had promised to clean the river to bathing standards by 2025.
Delhi-NCR AQI Nears 'Severe' Levels In Several Areas; Average Remains 362 How 'Severe' Air Pollution In Delhi Is Leading To Digestive Disorders Video: Toxic Foam On Yamuna In Delhi Raises Concern As Chhath Puja Begins Aligarh Muslim University A Minority Institution? Supreme Court's Key 4:3 Verdict Elon Musk Replies To 'We Need Your Help Removing Trudeau' Post "Did Entire World A Favour": Minister On Why India Buys Russian Oil DY Chandrachud's Last Working Day: What Do Chief Justices Do After Term Ends 2024 Maruti Suzuki Dzire Bags 5-Star GNCAP Rating, Delivers 25.71 Kmpl These Foods Rich In Healthy Fats Can Help Lower Bad Cholesterol Track Latest News Live on NDTV.com and get news updates from India and around the world.