More than 2,100 large or medium industrial units across Delhi-NCR, around 91% of such units across the region, have failed to comply with stricter particulate matter (PM) emission norms, including installation or retrofitting of air pollution control devices (APCDs), which were to come into force from August 1, The Indian Express has learnt.This prompted the Commission for Air Quality Management in National Capital Region and Adjoining Areas (CAQM) on Thursday to defer the deadline by two months — until October 1 — after industries cited rising costs linked to the West Asia crisis, supply chain delays and shortage of technical agencies to assess existing systems.200-odd units complyOf the 2,321 industrial units identified for installation or retrofitting of APCDs, only around 200 had complied by July 31. The figure also included those pending verification, The Indian Express has learnt.The remaining 2,121 or 91.4% units had not complied with the order, officials said.Industrial emissions in NCR are a precursor to secondary particulate matter, which, at 27%, has been identified as a major cause of winter pollution, followed by direct industrial emissions at 9%, according to CAQM records. Of the 2,321 industrial units identified for installation or retrofitting of APCDs, only around 200 had complied by July 31.Air pollution control devices are industrial filtration systems installed on exhaust stacks to capture emissions. The primary technology used include Baghouses, which use fabric filters to trap over 99% of dust; Electrostatic Precipitators, which utilise high voltage electricity to collect charged particles from massive exhaust volumes; Cyclone Separators, affordable pre-filters that use centrifugal force to spin out coarse ash and Scrubbers, which wash out fine dust and toxic gases using liquid sprays or powders.New deadlineThe CAQM, through an amendment on Thursday postponed the implementation of the revised PM emission standard of 50 mg/Nm³ from August 1 to October 1 for the identified industries.It said the decision followed recommendations of the Central Pollution Control Board (CPCB) and representations from industries and associations.The commission had identified 17 categories of high-polluting industries –including food processing units, textiles with boilers and metal furnaces, among others – ordering them to cap PM emissions at 50 mg/Nm³, down from the previous 80 mg/Nm³.Story continues below this adWhile large or medium plants had to comply by this limit – based on CPCB and Indian Institute of Technology (IIT)-Kanpur studies – by August, smaller units had to follow suit by October.The CAQM said that the revised emission limit remains “technically feasible and environmentally necessary”, and acknowledged that industries had faced practical constraints in meeting the deadline.Challenges citedAmong the challenges flagged by industry associations was the prevailing geopolitical situation, which they said had imposed an additional financial burden on them.Sources familiar with the discussions said manufacturers referred to disruptions arising from the ongoing West Asia crisis, which has increased costs and affected the procurement of components needed for pollution control equipment. According to the order, industries cited long delay in the supply of air pollution control devices, limited availability of agencies to carry out technical adequacy assessments of existing systems, and a shortage of laboratories recognised under the Environment (Protection) Act, 1986, to verify compliance with the revised emission standards. These factors had slowed installation, retrofitting and certification across the region.Story continues below this adWhile industry associations had sought an extension ranging from three months to one pollution season, the CPCB recommended extending the timeline until October 1, said officials.Sophiya Mathew is a Correspondent at The Indian Express, based in New Delhi. She joined the Delhi bureau in 2024, and has specialization in Integrated Multimedia Journalism from the Asian College of Journalism (ACJ), Chennai. Professional Background Core Beats: Her reporting is primarily focused on the Environment and Education. Specialization: She has gained recognition for her ground-level reporting on the Yamuna floodplains and the socio-economic challenges faced by those living on its banks. She also focuses on the disparities in Delhi's education system, ranging from elite private schools to government institutions and refugee education. Recent Notable Articles (December 2025) Her recent work has been heavily centered on Delhi's severe winter pollution crisis and the government's regulatory responses: 1. The Air Pollution Crisis "A tale of two cities: Delhi govt schools choke in bad air, private classrooms set up air filters" (Dec 20, 2025): A high-impact feature contrasting the "Clean Air Bubbles" in elite schools with the reality of government school students who are exposed to an equivalent of 17 cigarettes a day due to outdoor exposure. "Delhi sees season's worst air day, second worst December AQI in nearly a decade" (Dec 15, 2025): An analytical report on the meteorological patterns trapping pollutants in the NCR. "Delhi bans non-BS VI vehicles from outside: Why curbing vehicular pollution is key" (Dec 17, 2025): Explaining the science behind targeting specific vehicle vintages to lower particulate matter. 2. Enforcement & Regulations "No fuel at pumps in Delhi without valid PUC certificate from December 18" (Dec 17, 2025): Breaking the news on the environment ministry's strict "No PUC, No Fuel" policy. 3. Education Policy "Law to regulate school fee in Delhi risks becoming procedural, say parents" (Dec 13, 2025): Investigating the loopholes in the new Delhi School Education (Transparency in Fixation and Regulation of Fees) Bill, 2025. "Monsoon Session: Private school fee regulation Bill cleared after four-hour debate" (Aug 9, 2025): Covering the legislative passage of the controversial fee hike regulation. Signature Style Sophiya is known for her observational depth. Her reporting often includes vivid details from school corridors, hospital waitlists, or the banks of the Yamuna to illustrate how policy failures affect the city's most vulnerable residents. She is a frequent expert guest on the 3 Things podcast, where she explains the complexities of Delhi’s environmental laws. X (Twitter): @SophiyaMathew1 ... Read MoreStay updated with the latest - Click here to follow us on InstagramTags:delhiDelhi Pollution