Noise-induced Hearing Loss
An estimate of 11 million people are deaf or hard of hearing in the UK. Of these, the second-largest cause after age-related deafness is Noise-induced hearing loss. This can set in at an early age too with the number of younger people listening to high music on a daily basis.
Though you can’t always prevent deafness, taking the right measures to avoid loud noises and environments can help in the long run.
What is Noise-induced Hearing loss?
There are a variety of sounds and noises around us every day—sounds of the radio, music systems, people, traffic, etc. These sounds at a normal permissible level are safe and don’t damage hearing. But loud noises even for a short time can damage the inner ear and cause hearing loss. Exposure to loud sounds over a continuous period can progressively damage hearing. Loss of hearing in such scenarios is Noise-induced hearing loss (NIHL).
NIHL can occur in people of any age group including children and teenagers.
How does Noise-induced hearing loss occur?
Before we see how NIHL occurs, we need to understand the mechanism of hearing. The diagram below explains the series of events that occur as sound waves reach our ears.
- The sound waves reaching the outer ear travels through the narrow passage—ear canal and reaches the eardrum/tympanic membrane.
- The eardrum in turn vibrates and sends these vibrations to the 3 bones in the middle ear (called ossicles).
- These bones amplify the sound vibrations and send them across the snail-shaped structure filled with liquid (called cochlea).
- These sound vibrations then cause a ripple in the fluid of the cochlea creating a waveform.
- The waveforms travel along the basilar membrane which is a partition membrane in the cochlea containing sensory hair cells. Each of these hair cells detects a different pitch.
- As each hair cell detects a pitch that it is tuned to respond to, microscopic projections on the hair cells bump against an overlying structure and bend, which in turn causes pore-like channels to open.
- This creates an electrical signal due to chemicals rushing to the cells.
- The auditory nerve then carries these electrical signals to the brain, which will then translate it into recognisable sounds.
Now that we understand how the human ear works, let’s come back to how NIHL occurs. In most cases, NIHL is caused due to the damage and eventual death of the above-mentioned hair cells.
How loud is too loud
Decibels (dB) is the unit of measurement for sounds. As the number of Decibels increases, so does the noise.
Noises over 85dB can harm your hearing, especially for prolonged periods of time. Here is a list of average ratings of sounds to give you an idea:
- Whisper – 30dB
- Normal conversation – 60dB – 70 dB
- Washing Machine – 70dB
- Traffic – 85 dB
- Motorcycles – 80dB – 100dB
- Listening to music on full volume/Concerts – 100dB – 110dB
- Plane taking off – 120 dB
There are also many smartphone apps that help in measuring sounds and aid you in telling what sounds are too loud. If not, using common sense to get a grasp of loud noises and avoiding them is the best way to prevent the gradual loss of hearing.
How to avoid Noise-induced hearing loss
Minimise volumes while listening to music
Listening to music at high volumes is one of the major causes of deteriorating hearing especially amongst young people. To avoid damaging your ears:
- Keep volumes at a level where you can hear the music but not too loud that you drown out all other sounds.
- Use noise-cancelling headphones if possible. Again make sure that the volume is not too high.
- Take a regular break in between using headphones. A good interval would be a 5-minute break every 1 hour.
Avoid loud sounds and noises
- Whenever and wherever possible, try to avoid being near loud sounds.
- If you find yourself too close to any such source try and keep a distance.
Protect your ears during loud events
It is important to keep your ears safe during loud events such as concerts, sports events, clubs etc.
- Try to stay away from loudspeakers and other loud sources.
- Wear earplugs if the sounds are too loud.
- If exposed to loud sounds, give your ears time to heal and recover.
Take measures at work
If you find yourself surrounded by loud sounds at work you should speak to your manager or HR.
Employers are obliged by law to ensure safe environments for employees to prevent induced hearing loss. These include taking action to reduce noise exposure and providing protective gear in situations that require it.
More details on employer responsibilities as governed by the law can be found here.
Take a hearing test
- It is best to take a hearing test at the earliest possible if you think your hearing is failing.
- If you notice that you have to speak loudly to others, can’t hear what people close to you are saying, have ringing in your ears, etc, you have to take a test as soon as possible.
- If you work in an environment where you are regularly exposed to loud sounds, it is beneficial to take a regular check-up to ensure your hearing is safe and also take preventive measures.