Several cities in the sub-continent are smothered in toxic air, causing a major health emergency in the region.

Most South Asian cities have been struggling with air pollution, according to a real-time air quality ranking report by IQ Air Visual.

On Wednesday, October 30, Delhi became the most polluted city in the world with an Air Quality Index (AQI) rate of 422. As of today, it’s almost reached an AQI rate of 540, which makes it ‘hazardous’ according to the report. Additionally, in some districts, the AQI rate has reached more than 600.

AirVisual's report on World AQI ranking
AirVisual's report on World AQI ranking (Enes Danis / TRTWorld)
Indian schoolchildren cover their faces as they walk to school amid heavy smog.
Indian schoolchildren cover their faces as they walk to school amid heavy smog. (Sajjad Hussain / AFP)

New Delhi is followed by Lahore, the Pakistani city with an overall AQI rate of 269.

High level of fine particulate matter in the air has caused almost 60.000 deaths in Pakistan just in 2015
High level of fine particulate matter in the air has caused almost 60.000 deaths in Pakistan just in 2015 (ARIF ALI / AFP)

The index measures the air quality of the cities based on live tracking of the AQI all over the world. The AQI takes into account five main pollutants - particulate matter with a diameter less than 10 micrometres (PM10), PM2.5, ozone (O3), nitrogen dioxide (NO2), and carbon monoxide (CO).

Based on the classification of tracked data, AQI determines the quality of air in seven categories.

0-50: Good

51-100: Satisfactory 

101-200: Moderate

201-300: Poor
301-300: Very Poor
401-500: Severe
500 and above: ‘Severe-plus emergency’

The IQ Air Visual’s website reveals current situation of Delhi for the following days:

Delhi air quality and weather forecast. Source: IQ AirVisual
Delhi air quality and weather forecast. Source: IQ AirVisual (Enes Danis / TRTWorld)

The report states that everyone should avoid outdoor activities as it forecasts that the following days will be in the hazardous category.

The current situation in New Delhi and some other Asian cities has been undulating at the same level between ‘severe’ and ‘hazardous’.

As part of the emergency measures, the Delhi government has decided to shut schools until November 5 as the air quality in the national capital deteriorates further. 

If the air quality remains in the ‘severe plus’ and ‘hazardous’ category for more than 48 hours, emergency measures are taken under the ‘Graded Response Action Plan’ say Indian officials. 

Source: TRTWorld and agencies