Drivers complain of ringing noise in ears, obstruction in hearing, lack of clarity
“I hear a ringing noise in my ears after I finish my trip,” a driver complained to the audiologist at a screening programme for hearing loss at the K.K. Nagar depot of Metropolitan Transport Corporation recently.
Several other drivers felt that they had “some kind of obstruction in hearing or what they hear lacks clarity” for some hours after they completed their shift, which often is strenuous. Some of the conductors also had similar complaints.
The 55 drivers and conductors, who participated in the screening programme, are among the 18,000 MTC crew subjected to noise pollution daily. The MTC has 9,000 bus drivers and conductors each.
During the screening test, audiologist Akila Palani found that younger drivers experienced a “temporary threshold shift,” a condition caused by temporary exposure to noise, while senior drivers suffered a permanent loss of hearing at four kilohertz. Some of the crew members had “sloping sensorineural hearing loss” a result of long exposure to noise. The condition makes it difficult for a person to perceive speech in noisy surroundings. Surgeries or medicines or even hearing aids do not help in such cases.
“Some of them have been doing two shifts a day totalling 16 hours. We have advised an eight-hour shift with a rest of 16 hours for drivers, who have only a few years to go for retirement, and have symptoms of hearing problems,” she said.
Seven employees received earplugs to prevent further exposure to noise. The earplugs were sponsored by the Lions Club of Madras Padi Shenoy Nagar, which organised the screening programme. President of the club A. Devarajan said the screening camp was part of its ongoing programme. Last year, it had organised a similar programme in T. Nagar depot and 75 employees were screened. In 2009, around 100 employees were screened at the Anna Nagar depot.
“Depending on the feedback from the drivers and conductors, we will have more such programmes,” Chief Medical Officer of MTC A. Rajakumari said. Based on the response, the Lions Club of Madras Padi Shenoy Nagar proposes to extend the screening facility to all the MTC depots.
ENT surgeon C. Jacinth, who was part of a research project on noise pollution, suggests that moving personnel to other departments on rotation would delay the process of hearing loss.
According to Ravi Ramalingam of KKR ENT Hospital and Research Institute, who did a study on the effect of noise exposure on city traffic police, some years ago: “In the United States, the recommended exposure to noise level at 90 decibel (the sound of a truck driving past) should be 2 hours and 30 minutes. As bus drivers and conductors are exposed to noise for about eight hours, it is almost definite that there would be hearing loss. There is need to check if the employees are wearing earplugs and regularly find out if it helps.”