Noise levels within limit near airport: DIAL data

Residents said the problem lay in measuring sound levels in day and night averages, contending the limits must instead be set for peak noise values recorded

The airport operator at Delhi’s Indira Gandhi International (IGI) airport has said that the average decibel level of noise created by aircraft in five south and south-west Delhi areas in the vicinity are within the prescribed norms, according to documents seen by HT.

The data shared by DIAL, which has been uploaded on its website too, shows out of the five stations set up, the highest average daytime and nighttime noise levels of 65.9dB and 41.9dB were recorded at Sector 19, Dwarka, on March 2 and 19 respectively. (HT Photo)

The operator — Delhi International Airport Limited (DIAL) — said that it installed noise monitoring terminals (NMTs) or real-time devices to measure aircraft noise at five locations in the approach path of flights — Vasant Kunj, Hauz Khas, RK Puram, and sectors 24 and 19 in Dwarka. DIAL added that noise levels in March ranged from 41.8 decibels (dB) to 65.9dB between 6am and 10pm and from 41dB to 63.9dB between 10pm to 6am, which was within the permissible limits.The permissible limit for daytime is within 70dB and for nighttime it is 65dB, according to CPCB.

However, residents said the problem lay in measuring sound levels in day and night averages, contending the limits must instead be set for peak noise values recorded.

”DIAL is now conveniently displaying the data related to aircraft noise levels recorded... of runway approach and departure funnel of Delhi airport on its website... This information can be accessed by visiting the website at https://www.newdelhiairport.in/ where the aircraft noise levels recorded by DIAL are visible,” said the operator’s report dated May 1, a copy of which HT has seen

This data will now be uploaded on the airport’s website monthly, it added. The data is part of a report submitted by DIAL to the National Green Tribunal (NGT) said the agency was measuring real-time ambient noise in a 15km radius of the airport to assess the possible impact of flights on neighbourhoods located in the vicinity. This is being done following complaints by locals the frequent flights disrupting sleep and impacting people’s health.

NGT has been hearing an execution application filed by Vasant Kunj resident, Anil Sood, last year, alleging that noise pollution levels exceeded norms in areas near the airport. Sood said the problem is particularly acute at night with the frequent movement of flights, disrupting the sleep of children or the elderly.

The data shared by DIAL, which has been uploaded on its website too, shows out of the five stations set up, the highest average daytime and nighttime noise levels of 65.9dB and 41.9dB were recorded at Sector 19, Dwarka, on March 2 and 19 respectively.

At night, too, the highest average decibel value was 63.9dB at Sector 19, Dwarka, on March 30. The lowest nighttime average was 41dB at Sector 24, Dwarka, on March 14. While daytime readings occur between 6am and 10pm, night-time measurement are taken between 10pm and 6am. “The data showed the average decibel levels and not the highest values recorded when a flight directly passes overhead. The problem occurs mainly at night,” Sood alleged.

He had submitted his findings last October using a noise monitoring device to measure decibel levels in Vasant Kunj. The report, submitted to NGT, shared data from September 19 to October 19, 2023, suggested a maximum dB reading of 88dB on October 19 at around 7pm.

Rejimon CK, a resident of Sector 22, Dwarka, barely 2km away from parallel runways 29/11R and 29/11L, said he installed soundproof windows in his apartment. “Flights land and take off every minute... We need noise breakers installed in the vicinity accordingly,” he said.