NEW DELHI: Acoustic cameras at busy intersections may help catch honking drivers by alerting authorities and locating the source. Purpose, an organisation working on social development issues, on Wednesday conducted a trial run of the cameras at the busy stretch near AIIMS .“As part of the Hands Off The Horn (HOTH) campaign, we conducted a demonstration of an acoustic camera at the traffic intersection outside AIIMS. The idea is to show the capabilities and uses of these cameras, which could potentially help identify violators. We are already in talks with the traffic police regarding their use,” Reecha Upadhyay, campaign director, HOTH, said.An organisation working on social development issues tested the feasibility of the camera in a dense traffic situation.“We wanted to see whether it is able to identify the sound source. Initially, it was catching all the sounds created by the vehicles. But after increasing the decibel level to 75 and above, it caught only the horns. These decibel levels are higher than advised by doctors. We have captured a video where one can see the violators,” Upadhyay said.The acoustic camera system, already in use in 40 Chinese cities, consists of a 32-microphone array, a high-definition camera, a display screen, a flash and a processing system. Once a car horn is pressed, the microphones zero in on the source of the sound. The camera then captures the image of the car’s licence plate and films a two-second video. In China, acoustic cameras have shown an accuracy rate of 92-95%.High decibel levels can cause health hazards, including partial or complete deafness, depending on age and exposure. On the World Hearing Index, which ranks cities according to noise pollution and hearing loss, a person living in Delhi has the deteriorated hearing capacity of someone at least 20 years older.In 2018, Delhi Traffic Police issued 24,993 challans for using the horn in no-honking zones. A fine of Rs 100 is marked for these zones, but cops say little can be done to enforce the law due to lack of equipment to measure decibel levels. An RTI reply revealed that traffic police has only 15 noise meters for the entire city.During a study in 2017, the Central Pollution Control Board found that incessant honking was the biggest source of noise pollution in a city like Delhi. Even areas near schools and hospitals, which are supposed to be no-honking zones, are not spared. Because of obstructive parking and sheer numbers, the traffic flow gets hampered and noise levels go up manifold.A study carried out by the Centre for Science and Environment (CSE) in 2011 showed that, in several commercial and industrial zones in the city, the noise levels were crossing the 100dB mark, while in residential areas, the ambient noise levels were close to 90dB during the peak traffic rush against the standard of 55dB.Last year, Delhi Traffic Police, working with the state government’s environment department, had identified 52 silence zones where honking is prohibited, adding to the 103 such zones that already exist in the capital, usually in and around schools and hospitals, and at busy intersections.The National Green Tribunal ( NGT ) had recently directed the Central Pollution Control Board to prepare a noise pollution map and a remedial action plan to solve the problem of noise pollution across the country.All state pollution control boards have also been directed to undertake noise level monitoring along with police departments concerned.