Delhi's air quality has slipped into "critical" levels according to the System of Air Quality and Weather Forecasting and Research (SAFAR).

Footage from November 6 shows a grey haze shrouded the city as an air quality index rating of 437 was recorded at 9 am. Recordings above 301 are considered "hazardous and a "health warning of emergency conditions: everyone is more likely to be affected," according to Airnow.gov.

The local government has shut primary schools for two days due to the high air pollution levels.

Delhi continues to be covered in thick haze as the air quality remains in the 'severe' category, data from the Central Pollution Control Board (CPCB) showed on Monday. This is the fourth consecutive day that the national capital recorded a 'severe' air quality. The overall air quality index (AQI) of Delhi was recorded at 437 at 9 am, according to CPCB data.The overall air quality in Delhi continued to remain in the 'critical' category on Monday morning, according to the System of Air Quality and Weather Forecasting and Research (SAFAR)-India.

Unfavourable weather conditions, coupled with factors like vehicle emissions, the burning of paddy straw, firecrackers, and various local sources of pollution, collectively contribute to the annual winter air quality crisis in Delhi-NCR.

As reported by the Indian Agricultural Research Institute (IARI) in New Delhi, a record-high number of 4,160 farm fires were recorded in northern India on Sunday, marking the highest count for this season.In an attempt to protect young children from the harmful effects of pollution, the Delhi government has made the decision to shut down all primary schools for a period of two days.