Delhi air quality deteriorates as revellers mark Diwali with illegal fireworks

Delhi's air quality deteriorated on Monday as residents celebrated Diwali with fireworks in violation of court orders. At 9 a.m., the city recorded a 'very poor' air quality index of 370, a level considered dangerous by the Central Pollution Control Board. Many areas within the 20 million-strong city reported readings exceeding 400, classified as 'severe'.

India's Supreme Court had previously mandated that only certified low-polluting firecrackers could be used during specific hours during the Diwali weekend. Residents in Delhi and Mumbai reported fireworks continuing well into the night. Images from Reuters TV depicted a smog layer enveloping India Gate, a central Delhi landmark near government buildings and parliament.

As of Monday, Delhi ranked third among the world's most polluted cities, according to Swiss group IQAir, with Lahore, Pakistan leading with an air quality index of 563, classified as hazardous. Pollution is an annual issue in northern India during winter, as cold, dense air traps vehicle emissions, construction dust, and smoke from crop waste burning.

The problem is exacerbated in big cities like Delhi due to high vehicle numbers and construction activity, causing many residents to suffer from respiratory issues. Delhi has experienced poor air quality for over a week, and imposed restrictions on Friday under a graded action plan, which included instructing schools to hold online classes, among other steps.