New Delhi: Delhi's air crossed into the "very poor" band on Monday and kept going. By 7 am on Tuesday the citywide average Air Quality Index stood at 331, up from 307 at the same hour a day earlier, with PM2.5 the main pollutant.
The spread across the city was wide and, in places, severe. Of 58 monitoring stations with valid readings, 57 recorded above 200 and 41 above 300. Eight crossed 400: Jahangirpuri at 449, Rohini at 429, Punjabi Bagh at 424, Alipur at 413, Vivek Vihar at 410, Bawana at 408, Delhi Technological University at 407 and Narela at 406. ITO was at 373, Burari Crossing 382 and Pusa 387.
The climb was steep. The index was 117 on October 31, 261 on November 1 and 324 by 4 pm on Monday. Noida averaged 307 and Manesar 302, both "very poor"; Gurugram stood at 284, Ghaziabad 259 and Greater Noida 213. Gajraula in Uttar Pradesh was the most polluted city in the country in the Central Pollution Control Board's data, at 399.
The Commission for Air Quality Management invoked Stage 2 of the Graded Response Action Plan across Delhi-NCR on Monday, citing unfavourable meteorology and forecasts of more very poor days. Stage 2 adds mechanised and vacuum road sweeping, water sprinkling with dust suppressants, anti-smog guns on traffic corridors, higher parking fees, staggered office timings and tighter checks on diesel generator sets. Coal and firewood are barred in hotel and restaurant tandoors. Resident welfare associations have been asked to give electric heaters to security staff to discourage open burning.
Enforcement is already visible at the borders. Delhi Traffic Police said 7,657 vehicles were checked and 609 turned back since Sunday for not meeting emission standards, with 433 challans issued for no-entry violations.
Stubble burning contributed 8.5 per cent of Delhi's PM2.5 on Monday, according to the Indian Institute of Tropical Meteorology's decision support system, and that share is forecast to reach 22 per cent by Thursday. Transport was the largest local source at 20.07 per cent.
Diwali falls on November 8. The Supreme Court has allowed approved green firecrackers on November 7 and 8, only between 6 am and 7 am and 8 pm and 10 pm.