Delhi often makes headlines as one of the most polluted cities in the world, but has the coronavirus lockdown starting March 25th dramatically cut pollution in the capital? News outlets have reported reductions in pollution, but reports of reductions in Beijing were later disproven by data on the ground. A new Smart Air analysis got […]
Category: Delhi
Recent Delhi Articles:
The Data-Backed Most Cost-Effective Office Air Purifier
Can a simple fan and filter really make air purifiers that can clean large offices? Seven years ago, Smart Air started when PhD student Thomas strapped together a DIY air purifier to survive a polluted Beijing winter. Founder Thomas Talhelm‘s first DIY air purifier Thomas published test data on the purifier showing that it […]

How Many Trees Need to Be Planted to Solve Delhi’s Air Pollution?
When Delhi’s air pollution spikes, netizens in the nation’s capital often bring up the solution of planting trees. For instance, this user on the question-answer site Quora asks “how many trees does Delhi need to combat its air pollution problem?” However, environmental research suggests that planting trees are an incredibly inefficient way to reduce Delhi’s […]

Did Delhi’s Air Pollution Drop 25% in 2019? What the Data Says
The Delhi government and Delhi Chief minister Arvind Kejriwal announced Delhi’s PM2.5 air pollution was down 25% in 2016-2018 compared to 2012-2014. Yet there is doubt. Thewire.in, for one, expressed skepticism about this claim. As data-driven nerds, we wanted to let the numbers answer this question. So we dug into the Delhi PM2.5 data […]

Did Bangalore’s Air Quality Get Better in 2018?
Analyzing air quality data from the Berkeley Earth Project, Smart Air found that Bangalore’s air quality worsened by 7% in 2018 compared to 2017. This puts Bangalore at about 4 times the World Health Organization’s annual limit. Bangalore Air Pollution by Month Breaking down the data by month reveals exactly when air pollution was […]

Is Beijing or Delhi Air Worse?
Beijing and Delhi often make headlines for air polluted cities, but which city has worse air? I wanted to get some hard numbers on how the two cities’ air quality compare. The Data To do that, I analyzed PM2.5 data from the US Embassies in Delhi and government monitors in Beijing from 2015 to […]

Smart Air Provides Clean Air to Automobile Giant Ford
Right after moving to their new office in the Chimes building in Gurgaon, Ford India was experiencing problems with outdoor particulate pollution (PM2.5) and chemicals (VOCs) off-gassing from new furniture, carpets, paints, and other remodeling work. To tackle these problems and protect the health of their staff, Ford India reached out to Smart Air in […]

While Air Quality Improves in Other Major Cities, These Two Cities Worse in 2018
New analysis from Smart Air finds that 2018 was a good year for air quality for India’s major cities. Air quality was flat or down in three of five cities—Delhi, Hyderabad, and Chennai. Yet two cities saw air pollution rise significantly. PM2.5 pollution was up 17% in Kolkata, exceeding nine times the World […]

Exactly How Much Does Diwali Harm Delhi’s Air?
News reports this year suggested that people are now more aware that fireworks increase Diwali air pollution in Delhi, and there were reports of reduced sales of fireworks. But with 22 million people, Diwali must go on. So that got me to thinking: just how much does Diwali pollute our air? To get to the […]