Pollution levels in the NCR remained in the "serious" category during the third day of Sunday due to a combination of unfavorable weather conditions that kept dangerous pollutants from the firecrackers used during the Diwali and increased the campfire in Punjab and Haryana suspended in the air. several experts that control the quality of the air.
But the Central Control Council for Pollution (CPCB) said the improvement was likely on Monday with the speed of surface winds, which were also insignificant during the last three days, which is expected to resume.
Delhi's air quality index (AQI) on Sunday, according to the average 24-hour CPCB launched at 4 in the morning, was 405. All NCR cities, including Noida, Gurugram, Ghaziabad and Faridabad, were in the "severe zone" "People have difficulty breathing and doctors recommend that physical activity be kept to a minimum.
In the last 72 hours, air quality in the city was between 401 and 420. This is the first time AQI has remained "severe" for three consecutive days, indicating that the worst will not end the region that immerses in an emergency of Public health every winter.
An AQI value between 0-50 is classified as good, 51-100 satisfactory, 101-200 moderate, 201-300 poor, 301-400 very poor and 401-500 severe. If the AQI violates 500 for a period of 48 hours, emergency measures have been implemented in accordance with the classified response Action Plan (Grap) to combat pollution.
These more serious steps include the prohibition of the entrance of trucks, the activity of construction, the blockade of the schools and the impartial scheme of rationing of highways.
"No other action at this time has been proposed. According to the input received from the government's early warning system, air quality may increase slightly on Monday, leading pollutants trapped in the air. Pollution levels were" severe "mainly due to The accumulation of contaminants of firecrackers that scratch Diwali and smoke from stubborn burns, which are not dispersing due to cool and cold wind conditions, "said Sunita Narain, a member of the Supreme Court named Environmental Pollution [Prevention and Control] Authority (EPCA).
On Saturday, EPCA extended some "severe" measures: the ban on the entry of trucks within the city limits, construction activities and the closure of industries that use coal and biomass until November 12 under the advice of a working group of CPCB. These measures can also be invoked if the levels of deadly particles – PM2.5 and PM10 – cross 300 and 500 micrograms per cubic meter.
The levels of PM 2.5 and PM 10 on Sunday were recorded at 271 and 439 compared to the security limits of 60 and 100 respectively.
"According to the forecast of air quality, the AQI can fluctuate between" severe "and" very poor "with only a marginal improvement expected on Monday. Until now, Delhi is not able to disperse local emissions from 7 to November 7th [during Diwali] and those of scratch burns that have been accumulated due to lack of adequate wind speed. With a bit of sun and light wind speed, AQI can improve the "very poor" on Monday after the task team will review the measures, "said a senior CPCB official who asked not to be named.
He added that the quality of the air has also been "severe" because the "mixing height" (the rapidity with which contaminants can be dispersed) increases during the day but falls at night due to a temperature drop. The minimum temperature on Sunday was 12 degrees Celsius, two notes below the average.
"The amount of smoke contaminants from scratch burns in the neighboring states, which mainly contributes to the fact that the levels of PM2.5 were around 13%. Even when local emissions are controlled, smoke reaches New Delhi With the northwestern winds of Punjab and Haryana it is again contaminated. In addition, the cold and weak winds along with the fog produce a thick cloud cover, not allowing pollutants to disperse, "the CPCB official said.
Published for the first time: November 11, 2018 23:13 IST