JOIN USBut prolonged exposure to loud noise kills the delicate hair cells of the inner ear and the resultant hearing loss is so insidious that a person does not become aware of it till the damage is done.
The noise levels in most urban areas are dangerously high. Just observe around you and the variety of noises in modern life is astounding. Phones trilling, music systems blasting, vehicles blaring, construction activities, the list can go on. While the central pollution control board permits a 55 dB (A) noise level in residential areas during day time, studies have demonstrated these levels to be much higher. With cities never sleeping, silent nights have become elusive too. The softest sound that a healthy young ear can detect is 0 dB. Normal conversational speech is around 60 dB loud.
Any sound above 85 dB has the potential to harm our ears. Since sound is measured in a logarithmic scale, the perceived loudness doubles with every 10 decibels. The rule of thumb is louder the sound, the less time of exposure required to cause damage.
Serious effects
What are the dangers of noise? Permanent hearing loss, raised blood pressure, altered metabolism among the more serious ones and ringing in the ears, irritability and disturbed sleep all of which can lead to more serious effects if left unattended. While all of us are familiar with the temporary hearing loss and ringing when an ‘atom bomb’ goes off close to our ears on Diwali, what we don’t realise is the effect of noises that is less loud but never the less dangerous in the long run.
While we generally think of noise as unwanted sound, music and other recreational noise can be dangerously high too. The present ipod listening, gaming and constantly-on-cell phone generation is particularly susceptible to noise induced hearing loss. Not only have the ambient noise levels increased due to urbanisation, they are exposing their ears to louder levels of noise and for longer periods of time. Increasing noise exposure has also been linked to poor academic performance.
What are the warning signals that loud noise is damaging the ears? Ringing in the ears and an inability to understand speech clearly after noise exposure. Tiny hair cells in our inner ear get damaged due to noise. While initially these hair cells recover over time, with very loud sounds or with prolonged exposure, the damage and the hearing loss become permanent.
So as the world observed this international noise awareness day on April 27, what can citizens do? Becoming aware of the noise in our surroundings is the first step. Eliminate the unnecessary ones and lower the volume whenever feasible. Buy equipment that is less noisy. Keep instruments and vehicles well serviced/well oiled, distance yourself from the source of noise, use ear protective devices. Do not honk unnecessarily. For personal music systems, buy those with automatic cutoff levels. Do not raise their volume when in noisy surrounding, if you can’t hear a person calling your name from three feet away, you are listening to music at very high intensity levels. While this may not be music to some ears, respect your neighbours’ right to silence too.
People take precautions to guard against air and water pollution because they are aware. Awareness about noise pollution is woefully inadequate. The government’s rules and regulations regarding noise are often broken with impunity. A surprising exception was the report of slapping of a whopping Rs 5.75 crore fine by the Mumbai police on the IPL organisers. These cricket officials were booked for the loud match celebrations which used firecrackers and loudspeakers beyond the 10 pm deadline! This was in 2010 and it is anybody’s guess whether the fine was paid.