Delhi Winters are notoriously known for bad levels of air pollution, but we often hear that air gets cleaner come Spring. We were curious what was happening in our own backyard, so we put out our Dylos Particle Counter on a rooftop near our Saket office. The Particle Counter measures particle counts between 0.5 to 2.5 micron in size per 0.01 cubic ft. From this number, we can estimate PM 2.5, which are microns approximately 30 times smaller than human hair. PM 2.5 is considered harmful to human health since these particles can get lodged deep into the lungs and cause respiratory and cardiovascular problems.
Here is the data from November 2015 – March 2016. Though air pollution levels do drop in March, notice that the month still had zero days of ‘good’ or ‘moderate’ quality air. Due to fluctuations in hourly air quality, some of the maximums in March are higher than the average pollution levels between November and February.
Though Delhi air may get better in the Spring, it doesn’t improve enough to be considered clean or healthy. Keep those masks and air filters handy!