By Erica du Toit, National Council of and for Persons with Disabilities
We are surrounded by daily noise that affects our hearing, without realising it.
We often accept loud noise in traffic, shopping centres, restaurants, sports matches and music concerts as normal.
The ear-splitting sound of firecrackers, drums and vuvuzelas is met with quiet resignation.
But we’re unaware of the detrimental consequences these have on our ears and hearing.
Exposure to high levels of noise every day can have serious implications.
How loud is too loud?
Sound is measured in decibels (dB).
A soft sound like a whisper is 15dB, a normal conversation is 60dB, and street sound can vary between 70 and 90dB.
The noise level of a lawnmower is approximately 90dB, a Boeing on take-off is 140dB, music concerts are most often higher than 120 dB, while gunshots and fireworks are 140dB.
All sounds higher than 85dB are harmful to the human ear.
An ordinary hand-held hairdryer emits approximately 85-90dB of sound, with possible hearing damage after 8 hours.
For every 3dB increase, the exposure time is halved, so 88dB means a safe exposure time of 4 hours, 91dB is 2 hours, 94dB is 1 hour, and so on.
Exposure to sounds higher than 110dB can cause permanent damage in less than 15 minutes.
How does damage occur?
The inner ear contains approximately 20,000 hair cells. When hair cells are damaged, unreliable messages are sent to the brain.
The inner ear can be compared to a carpet in a passage. If more people walk on it, it will become threadbare much sooner.
However, a carpet in a passage can be replaced, but the damage to hearing is in most cases irreversible.
The World Health Organisation estimates that around 20% of the global population experiences some form of hearing loss.
This means that approximately 12 million South Africans struggle with hearing loss.
What are the warning signs?
In adults, a number of warning signs can indicate loss of hearing:
- ringing or buzzing in the ears;
- muffled sound;
- difficulty in following a conversation when background noise seems to intrude;
- turning the television or radio louder;
- finding it difficult to hear the sound of the telephone, a cricket or the doorbell;
- struggling to hear when one can’t see the person’s face;
- or when dimly lit areas make communication difficult;
- tendency to blame others for mumbling or speaking indistinctly.
These are all indications that an audiological assessment or hearing test is required.
The struggle to hear and communicate can become disruptive, and some people choose to avoid social gatherings, meetings, sporting events, and church services.
Noise and sound pollution not only causes discord between parents, children, friends and neighbours – it can also contribute to high blood pressure, stress, sleep disorders and deafness.
Deafness, in turn, is a factor in social isolation, cognitive decline and a greater risk of falling.
Preventing noise-induced hearing loss in adults
• Move further away from speakers if possible
• Wear adequate hearing protection, such as foam earplugs or a variety of other types of earplugs if the music is too loud.
• If you use headphones, play the music at safe listening levels. If you can’t hear other people talking when you wear headphones, or if others have to shout at you to be heard from a metre away, it’s too loud. This only applies to in-ear headphones.
• Be aware of noise levels in the environment and limit the amount of time spent in those areas.
We live in a world of sound and noise. It is important to make time to listen to and enjoy the silence. Do so before you possibly forget what it sounds like or before you are unable to hear any longer.
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Erica du Toit is with the National Association for Persons with Disabilities
The views expressed in this opinion piece are those of the author, who is not employed by Health-e News. Health-e News is committed to presenting diverse perspectives to enrich public discourse on health-related issues.
