Lahore on Sunday again crossed the threshold of the worst hazardous air quality levels in different areas of the city.
According to air pollution data, the provincial capital recorded the hazardous particulate matter (PM) rating of 427 at Township and 418 at Allama Iqbal Town. While the average air quality of the city at the index was measured at 343.
AQI as high as 151-200 is considered unhealthy, while an AQI rating between 201 to 300 is more harmful and AQI over 300 is dubbed extremely hazardous.
According to experts, an increase witnessed in air pollution in winter, change in the wind speed, wind direction and sliding minimum temperature increases air pollution.
The air becomes heavier in the winter as compared to summer, causing poisonous particles in the atmosphere to move downwards and making the atmosphere polluted. As a result, a layer of polluted particles, including large amounts of carbon and smoke, covers a city.
The smoke produced by burning crop remnants, factories and burning coal, garbage, oil or tyres enters the atmosphere and the effects of this appear at the onset of winter and remain till the season’s end, experts said.
Thus, air pollution reaches to extremely dangerous levels, severely compromising the air quality.
The AQI is calculated based on five categories of pollution: ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.