New Delhi: On October 29, Delhi’s Air Quality Index breached 400, putting it in the ‘Severe’ category. When air quality touches the ‘Severe’ level, it can not only seriously impact people with existing diseases, but also affect healthy people. Though air quality has improved marginally and is now in the ‘Very Poor’ category, the national capital will continue to struggle with poor air quality due to factors including increased stubble burning in neighbouring states, according to government reports.In light of such deteriorating air quality, the Delhi government implemented Stage III of the Graded Response Action Plan (GRAP) on October 29. This means that more restrictions are now in place – such as a strict ban on construction and demolition except in some cases – to ensure that such activities do not worsen pollution levels.Stubble-burning and slow windsAccording to SAFAR, the Indian government’s System of Air Quality and Weather Forecasting And Research, stubble burning contributed to just 7% of Delhi’s fine particulate matter levels (PM2.5, an air pollutant emitted during construction and fossil fuel combustion) on October 28. This, however, jumped to 26% on October 30. This is a higher level of contribution to PM2.5 levels when compared to the same day last year.Stubble burning – when farmers burn crop residue in fields to prepare for the next sowing season – is one of the main reasons why Delhi experiences poor air quality in the winter months starting from October. Punjab alone recorded 1,761 cases of fire on October 30, as per the bulletin. On the same day, the Punjab government also suspended four agriculture officers for dereliction of duty, and not ensuring the prevention of stubble burning on the ground.A farmer burns paddy stubble, as pollution levels rise across Delhi NCR due to Diwali celebrations, on the outskirts of Jalandhar, October 25, 2022. Photo: PTIAlong with increased stubble burning, slow wind speeds are also contributing to the worsening air pollution levels in the city. A bulletin released by the government’s Air Quality Early Warning System for Delhi on the morning of October 31 said that wind speed across the day in the city is at around 4-8 km per hour. Wind speeds less than 10 km per hour combined with other factors is “unfavourable for dispersion of pollutants”, the bulletin noted.As per the bulletin, Delhi will therefore continue to experience poor air quality. It warned that air quality in the city is “likely to deteriorate” and remain in the Very Poor to Severe category on November 1. That’s the outlook for the next six days too. As per the System, the Air Quality Index in Delhi on October 31 was 349 (at 12:52 pm), in the ‘Very Poor’ category.Earlier, air quality in the city dropped to ‘Severe’ levels in mid-September but this was primarily due to the lack of winds, which traps pollutants and prevents them from dispersing away, air pollution researchers had told The Wire. After the city’s Air Quality Index breached 400 on Saturday and the Early Warning System predicted a further deterioration in air quality, the Commission for Air Quality Management in NCR & Adjoining Areas (CAQM) decided to implement Stage III of Graded Response Action Plan (GRAP) after an emergency meeting on October 29.More measures in placeThis means that several additional restrictions will now be in place to ensure that certain activities which can worsen pollution levels are not allowed. This includes a strict ban on construction and demolition activities in the whole of the National Capital Region (NCR). Exceptions include activities in essential service systems such as at rail and metro stations and hospitals.Other activities that are banned as part of deploying Stage III of the GRAP include movement of vehicles on unpaved roads, and cutting and fixing tiles, stones and other flooring materials. There is also a strict ban on the operation of industries that are not using permitted, cleaner fuels (as per the standard list of approved fuels for NCR). Some in this category, such as rice processing units, can operate only for five days a week till December 31.The CAQM advised various agencies responsible for implementing these measures under the GRAP, as well as the Delhi Pollution Control Committee and Pollution Control Boards in the NCR, to ensure strict implementation of these measures. The CAQM directive also advised citizens to use public transport or share rides to work, work from home if possible and not use coal and wood for heating purposes. It also recommended that individual house owners provide electric heaters to security staff for the coming winter to avoid open burning.A metro train runs on a track as vehicles ply amid low visibility due to a thick layer of smog, in Gurugram, October 29, 2022. Photo: PTIMeanwhile, Delhi environment minister Gopal Rai said on Sunday that the government has set up 586 teams to ensure strict implementation of the ban on construction and demolition activities in Delhi.“We have held a meeting with all construction agencies in the capital and government departments concerned, including the PWD, MCD, Railways, DDA and the Delhi Pollution Control Committee. We have decided to implement the ban on construction and demolition activities in the city,” the minister said.The Delhi Fire Services also said on October 30 that it has begun sprinkling water at 13 hotspots – including Dwarka, Mundka, Anand Vihar and Okhla – to combat the rising air pollution. On the advice of the CAQM, Stage I of the GRAP had first come into effect on October 5, and Stage II, on October 19.