Smog towers are structures designed as large-scale air purifiers to reduce air pollution. Smog towers work on the principle of HEPA filtration or air ionisation technology to remove PM2.5 particles. That is, air flowing through a smog tower passes through a filter to provide clean air coming out of it. These methods of cleaning air are scientifically well established and used widely for cleaning indoor air where the air exchange with the outdoors is minimal. The first prototype of a smog tower was built in 2017 by Dutch artist Daan Roosegaarde in Beijing as a demonstration and art project that Converts the carbon in filtered particles into diamonds. The device will be able to take in air from all 360-degree angles and generate 1,300,000 cubic metres of clean air per hour. The smog tower sucks the polluted air, which is purified by the multiple layers before re-circulated into the atmosphere.  To purify the air; the highly effective H14 grade Highly Effective Particulate Arrestance (HEPA) filter would be used. This filter can clean up to 99.99% Particulate Matter (PM) present in the air with the help of pre-filter and activated carbon.