The Supreme Court-appointed EPCA has lifted the ban on the entry of heavy vehicles into the national capital Delhi on Tuesday even as a thick haze engulfed the city. Now with this the air quality is remaining in the "severe" category. Authorities said that rains in some parts of the national capital have made the air heavier and increased pollution.

The EPCA also said that heavy vehicles would now carry out in the city on normal timings between 11PM to 6 AM.

Meanwhile, a new study by the ASAR Social Impact Advisors said about 89 per cent people in Delhi feel uneasiness due to bad air quality and most of them consider motor vehicles. This organization works on social and environmental issues and said that felling of trees are major reasons behind pollution.

For the study around 5,000 people in 17 cities were interviewed. It is found that the top four reasons behind bad air quality were pollution caused by motor vehicles (74 per cent), industrial units (58 per cent), tree cutting (56.9 per cent) and construction (48.2 per cent).

The overall air quality index (AQI) was recorded at 411. It drops in the "severe" category, according to data from the Central Pollution Control Board (CPCB).