This month, New Delhi suffered a sharp increase in air pollution, leaving its residents struggling to breathe. The World Health Organization said that New Delhi is the most polluted city in the world and, this month, it has only worsened, reported Quartz.

Warnings are typically given in moments of high pollution or smog to tell residents to stay inside. However, the situation is so severe that doctors have advised anyone with heart or lung disease to leave the city. Schools may also be closing until the smog clears, noted Quartz. The Delhi High Court said that living in the city feels like living in a gas chamber, reported the BBC.

The pollution reading in New Delhi has reached 500 units, the highest reading recordable on the Indian Pollution Control Board's scales, reported NDTV. This is 10 to 16 times higher than safe air quality levels. According to the U.S. Embassy's monitoring station, which uses a different scale, the air quality index is at 286, which is very unhealthy, said Quartz.

The air quality tends to worsen in New Delhi in the winter, due to poor neighborhoods burning leaves, rubber and garbage to stay warm, reported NDTV, and smoke from crackers for the festival of Diwali did nothing to aid the situation, reported BBC.

"There has been a seven-time increase in pollution levels since Oct. 1," said Anurita Roychowdhury, executive director at the New Delhi Centre for Science and Environment. In response to this problem, the government is planning on removing all commercial trucks that are older than 15 years from the road by April 2016, reported Quartz. Private vehicles will also be limited. Vehicles with odd- and even-numbered registration numbers will only be allowed on the road on alternate days, reported the BBC.