Air pollution levels in the national capital are expected to hit their highest mark yet on Thursday, according to System of Air Quality and Weather Forecasting And Research. A scientist with the organisation said the PM2.5 rating, which measures small particulate matter, was going to hit 252, while the PM10 rating, for larger pollutants, will touch 413. This is more than four times the safe limits of 60 micrograms per cubic metre for PM2.5, and 100 for PM10.

The pollution levels are expected to come down after November 7, NDTV reported. Delhi has been engulfed in a thick haze over the past few days, with large-scale crop burning in Punjab and Haryana making matters worse. The Delhi government on Wednesday asked the Centre to intervene in these neighbouring states to reduce smog levels in the capital. Delhi is India’s most polluted city.