Odd Even Rule In New Delhi Reduce Air Pollution:Delhi Transport Corporation (DTC) buses stuck to a lane on the left, small bands of school children lined the roads with placards, civil defence volunteers stood at traffic junctions with flowers. There were visibly fewer cars on the road and for 12 hours, most of their licence plates ended with a 1, 3, 5, 7 or a 9. 

Air pollution vacillated, reducing between 8am and 2pm before rising again, on Day One of the Delhi government’s odd-even experiment to check pollution in the national capital, even as experts said it is premature to jump to conclusions with just 10 hours’ data.

Odd Even Rule In New Delhi Reduce Air Pollution

Between 8am and 2pm, PM 2.5—particulate matter with diameter less than 2.5 microns—levels fell from 194 μg/m3 (microgram per cu. m of air) to 188 μg/m3, according to a report by the System of Air Quality and Weather Forecasting and Research (SAFAR), ministry of earth sciences.By 6pm, PM 2.5 levels were at 198 μg/m3, which is considered very poor quality as the optimum level is 60 μg/m3.

As part of Delhi’s odd-even experiment to control the alarming levels of pollution, between 1 and 15 January, private cars with licence plates ending in odd numbers will be allowed to ply on odd dates and the ones with licence plates ending in even numbers will be allowed to ply on even dates. The rule applies from 8am to 8pm.

On Thursday and early Friday, the report said air quality deteriorated probably due to vehicle movement and firecrackers, combined with a fall in temperature by at least 1.5 degrees Celsius, leading to a rise in PM 2.5 levels. There was roughly a 10% reduction in PM 2.5 levels, which, according to SAFAR, could be due to reduced emissions.

“However, again after 2pm, why there was an increase in PM 2.5 with respect to the previous days’ levels needs to be examined scientifically,” said Gufran Beig, project director, SAFAR.

Beig added that it was still premature to conclude anything with just 10 hours’ data available for comparison.According to SAFAR, three factors contribute to changing PM 2.5 levels as Delhi implements the odd-even experiment.

These include cool temperatures, which mean higher air pollution; slow wind speed, which can mean stagnant air pollution and, finally, man-made emissions out of which 40% are from the transport sector.The pollution monitoring agency concluded that an around 15% reduction in PM 2.5 can be expected because of the odd-even experiment.