Quality, not quantity to be focus of air monitoring this time

Data to be collected in a way that will make comparison of pollution levels easier across the city.File photo  

: Not much was learned about the way pollution behaved during the trial phase of odd-even in January except that the air quality monitoring plan will have to change.

Learning from mistakes made in the first round of odd-even, the Delhi government will be expanding its air quality monitoring during round two, which is starting on April 15.

Two major problems emerged from the mobile monitoring done last time – firstly, there was no way to isolate the impact of weather conditions, and secondly, data was collected on only one day for each of the 246 locations, making comparison impossible.

This time, however, the quality of data will be more important than the number of locations covered. The government’s emphasis last time was on number of locations, with CM Arvind Kejriwal setting the target of 200.

“This time, we may reduce the number of locations. We will start collecting data five days before odd-even kicks in and continue to do so during the 15-day period. We will cover the same location multiple times, so that we can gauge the impact,” said Ashwani Kumar, Environment and Forest Department Secretary and Delhi Pollution Control Committee chairperson.

Mr. Kumar explained that to isolate the impact of weather conditions, areas in Noida and Gurgaon will also be studied. By taking samples from Delhi, where odd-even will be in force, and from across the border, where the number of cars will stay unchanged, the DPCC will be able to see the difference between pollution levels while weather conditions remain the same.

The pollution-monitoring vans, with mounted samplers, will have a circular route that will take it from within Delhi to locations in UP and Haryana.

“There were certain questions raised last time that we will be looking to answer this time. We will isolate the impact of weather conditions by going beyond Delhi. We will look at day-to-day changes as well as place to place changes,” said Mr. Kumar.

This time, air quality data will be taken on the road as well as some distance away, which will help in determining the exposure levels for road commuters.