Delhi air quality plummeted to severely bad levels on Thursday under the impact of unabated bursting of crackers on Diwali, as people in most parts of the region in and around the national capital openly flouted the Supreme Court guidelines .
According to the System of Air Quality and Weather Forecasting and Research (SAFAR) under the Union ministry of earth sciences, the Air Quality Index (AQI) in Delhi and adjoining regions at 4 pm averaged over 500 (it is a measure of the concentration of five pollutants). This was almost 10 times more than the permissible outer limit. The morning after Diwali, it had risen to over 600, making it among the worst air quality seen this year in and around the national capital. A thick cover of smoke and haze gripped the capital since morning.
An AQI up to 50 is considered ‘good’, 51 to 100 ‘satisfactory’, 101-200 ‘moderate’, 201-300 ‘poor’, 301-400 ‘very poor’, and 401-500 is ‘severe’. A reading above 500 is 'severe-plus emergency'.
The SAFAR analysis showed that impact of paddy stubble burning in adjoining states was nil on the AQI.
In recent weeks, Delhi doctors have reported an increase in the number of patients with respiratory problems due to a rise in pollution levels of vehicle exhausts, industrial gases and stubble burning to some extent.
Expert have advised people to avoid big physical activity outdoors, to shut windows and to frequently wet-mop floors in place of vacuum cleaning or dusting.
The SC had allowed people to burst firecrackers from only 8 pm to 10 pm on Diwali and other festivals. And, only allowed manufacture and sale of 'green' crackers, which have low emission of light, sound and harmful chemicals. In fact, Delhi Police had issued no legal licence for sale of crackers, reasoning that none of the varieties available met the court's standard. The Delhi government has started sprinkling water on roadside trees and major thoroughfares, to lower the impact of pollution.