According to the Delhi government, air and noise pollution decreased this Diwali.
Delhi Pollution Control Board officials, who monitored pollution at 40 locations, said people were increasingly becoming aware of the problems caused by crackers.
DPCC figures showed that noise pollution on Diwali night was between 69.7 db and 88.3 db -- higher than the prescribed limit of 50 db. It was 91.2 db last year, and 100 db in 2001, according to the officials.
Crackers cause a huge increase in pollutants. Respirable Suspended Particulate Matter and Suspended Particulate Matter -- the two main indicators of pollution -- rise.
According to the DPCC figures, the SPM level decreased at 20 out of 40 locations as compared to last year.
The highest SPM level of 4,772 microgram per cubic meter was recorded at Meera Bagh while the lowest of 1,068 microgram per cubic meter at Defence Colony. The prescribed limit is 200.
Last year, the highest SPM level was 4,051 in Karol Bagh and the minimum 1,634 in Rohini -- both in north Delhi. Though the highest SPM level has increased this year, it has decreased at most places compared to last year.
The highest RSPM level was 2,292 microgram per cubic meter at Meera bagh and minimum was 586 in Rajpur Road, near the Delhi University. The prescribed limit is 100.
Last year, the highest was 1,844 in Shanti Vihar and minimum was 614 in Rajpur Road. The highest RSPM level also increased this year, but decreased at most places compared to last Diwali.
Sulphur dioxide levels came down at 21 places, carbon monoxide at 27 places and nitrogen oxides at 13 places as compared to last year.
Based on the above figures, the officials called it an "environmental friendly" Diwali.
But some experts differed.
Leading environmentalist Iqbal Mallik, who is part of the anti-cracker campaign, said: "This was not a good Diwali. As compared to last year, it was worse."
She claimed that the government figures were fudged. The DPCC report said the maximum noise pollution level was 88.3 db. But Mallik said she recorded 125 db at Asian Games Village, an upscale south Delhi neighbourhood.
"The worse thing was that most people started bursting crackers after 10 pm. This was against the Supreme Court ruling. And the police and the government failed to enforce the order," said Mallik.
Police claimed to have fined around 500 people for bursting crackers after 1000 IST. The maximum punishment is imprisonment up to five years and fine up to Rs 100,000.
Many resident welfare associations also claimed that crackers were used till early Sunday.
Agreed Anumita Roychaudhury, head of the anti-pollution unit of voluntary group Centre for Science and Environment.
Roychaudhury said: "There were less noise this year as indicated by the DPCC figures. But this does not mean that people used lesser crackers. They may have used crackers of lesser decibels. We heard crackers bursting throughout the night."
Since the highest RSPM level increased this year, it indicated that a lot more needed to be done in the anti-crackers campaign, she said.
"It is difficult to say whether it was better Diwali than last year because we don't have the figures of the actual sale of crackers. SPM and RSPM level increase due to number of meteorological factors and not just crackers," she said.
"We are lacking a sustained anti-cracker campaign. We do it like a ritual just before the festival and forget it rest of the year."
The experts also criticised the government's decision to link crackers to the outbreak of dengue this year.
The Municipal Corporation of Delhi said that the smoke produced due to crackers would kill dengue mosquitoes. Therefore, there were lesser anti-cracker advertisements and policing this year.
Mallik said: "This is really disappointing. There is no scientific logic in it. The crackers' smoke does not kill mosquitoes.
"We were going in the right direction in the anti-cracker campaign and people were becoming aware but the government has no idea how to handle it."