New Delhi is closed due to smog: the authorities of the Indian capital, home to more than 28 million people, have announced that in the week of 15 to 21 November schools will remain closed, construction work will be halted for at least four days and public employees will work remotely.

The aim is to improve the now unsustainable levels of air pollution recently recorded in the capital, which are putting residents' health at risk.

New Delhi and the pollution problem

On Saturday 13 November, the authorities of the Indian capital announced the closure of schools "to avoid pupils having to breathe such polluted air", as explained by Delhi's chief minister, Arvind Kejriwal.

The previous day, New Delhi's air quality index – which measures the level of air pollution on a scale of 0 to 500 – set a new negative record, reaching 471 points. This was reported in the daily bulletins released by the Central Pollution Control Board. This is a threshold considered "hazardous" to human health, which can lead to serious health problems.

On the same day, the concentration of fine particles with a diameter of less than 2.5 micrometres, PM2.5, stood at 381 micrograms per cubic metre, a level also considered extremely concerning. For comparison, an acceptable PM2.5 value is just 12 particles per cubic metre.

Even before these alarming readings, the situation in New Delhi had been steadily worsening. In 2020, the city claimed the distinctly unwanted title of most polluted capital in the world for the third consecutive year, according to data from IQAir, a Swiss research centre that assesses air quality based on PM2.5 concentrations. Rome, meanwhile, ranked as the sixtieth most polluted capital in the ranking, which covered 92 cities.

Possible solutions

The situation in New Delhi is so alarming that the Indian Supreme Court has called for a lockdown and remote working to be imposed across the entire capital, with the specific aim of bringing air pollution levels down as quickly as possible. "A lockdown has never been imposed because of pollution — it would be a drastic measure", said Kejriwal, who nonetheless committed to considering the option.

For years, the local government has been battling against the air pollution problem. Last August, the city inaugurated its first "smog tower" (smog tower), a structure equipped with forty enormous fans that push one thousand cubic metres of air per second through a series of filters capable of halving the quantity of potentially harmful particles present within a radius of one square kilometre.

The construction of the tower cost two million dollars and therefore, according to many critics, purifying the entire city – which covers an area of more than 40 square kilometres – would represent an excessive burden on public finances. Meanwhile, the air in New Delhi remains unbreathable.