The government, however, admitted in the Lok Sabha that officials designated as the authority for the maintenance of ambient air quality standards of noise have not been provided with adequate instruments for measuring noise level.

In a written reply, Environment Minister Prakash Javadekar said that noise pollution has increased in Delhi and the National Capital Region.

"The analysis of data in Delhi reveals that ambient noise standards are being violated at nine out of ten locations and there is a fluctuating trend," Javadekar said.

He said all deputy commissioners and SDMs of revenue districts, assistant commissioner of police control room, all sub-divisional police officer including Railways and Airports, chairman and member secretary of Delhi Pollution Control Committee have been designated as the Authority for the maintenance of ambient air quality standards of noise.

"Sound level measuring instruments have not been provided to the above listed authorities. The Delhi Pollution Control Committee is requested to measure the noise level and report for further appropriate action.

"In case of complaint, field verification through department, police authorities and nearby inhabitants is done to ascertain the facts, as informed by Government of NCT of Delhi," the Minister said.

The officials have been designated as authority as per the Noise Pollution (regulation and control) Rules, 2000 under the Environment (Protection) Act, 1986 in the National Capital Territory of Delhi.