Turn down that volume

If the music playing through one’s ear piece can heard by one’s neighbour, then it is probably too loud. Noises that are too loud and last too long lead to hearing damage. photo by Rachel Mabala.

What you need to know:

According to the World Health Organisation, millions of people worldwide are at risk of hearing loss as a result of listening to too much, too loudly. According to the World Health Organisation, millions of people worldwide are at risk of hearing loss as a result of listening to too much, too loudly.

Many of us are guilty of constantly wearing earpieces at workplaces, home, class, or even when you are on the road stuck in insanely slow traffic. Beyond the earpieces, some people think if they do not sit directly under the booming speaker at a party, the music will be heard less.

In 2012, the World Health Organisation (WHO) released new estimates on the magnitude of disabling hearing loss. The estimates are based on a review of 42 population-based studies carried out up to 2010. According to WHO, 1.1 billion teenagers and young adults are at risk of permanently damaging their hearing by listening to “too much, too loudly”. Audio players, concerts and bars were pinpointed as posing a “serious threat”. WHO figures show 43 million people aged 12-35 have hearing loss and the prevalence is increasing.

The effects of this much noise can be damning to an individual thus the need to protect our hearing when we are exposed to loud noise. In order to do this, one must first understand and know which noises can cause damage to our hearing.

Sound levels
Sound is measured in units called decibels (dB). Decibel levels begin at zero, which is near total silence and the weakest sound our ears can hear. By comparison, a whisper is 30 decibels and a normal conversation is 60 decibels.

Any sound above 85dB which equates to the sound of city traffic at a close distance, can cause hearing loss, and the loss is related both to the power of the sound as well as the length of exposure. You know that you are listening to an 85dB sound if you have to raise your voice to be heard by somebody else.

Effects of noise
Dr Edward Turitwenka, an Ear, Nose and Throat specialist at Tays Consultation Clinic, says noise can cause effects on the body such as hearing loss, interference with sleep, annoyance, interference with work and can even increase blood pressure.

Dr Turitwenka explains that hearing loss from loud sound happens gradually and stealthily. Prolonged exposure to any noise at or above 85 decibels can cause gradual hearing loss. This is called Noise Induced hearing Loss (NIHL) which occurs when tiny sensory hair cells in our inner ears are damaged by noises that are too loud and that last for too long. This type of hearing loss is often a result of industry noise from factories, military and agro forestry activities such as cutting down a tree with a power saw.

Risk and exposure
“The damage to hearing is a product of intensity and length of exposure,” explains Dr Turitwenka.
The distance you are from the sound also matters. A sound gets louder as you move closer to the source and softer as you move away from it.

If you are far away from the sound, its intensity and potential to cause damage are much lower.
If the level of sound is 80dB or less, which includes the sound of a normal conversation or telephone dial tone, it is not likely to cause damage to hearing. Any exposure to 140dB sound (the level of sound produced by a jet engine or the sound of a gunshot) can cause immediate damage and actual pain to the ear. If the intensity of the sound is very high, damage can be instant as happens in sudden escape of steam.

Furthermore, he says if the exposure is 85dB lasting eight hours a day for five days a week, then within five years, hearing loss can be noticed. “In Uganda we use the rule of three so that for every three dB increase above 85 dB, the length of exposure should be halved,” says Dr Turitwenka.

If you are exposed to sound levels that are 85 dB only, the exposure time should be eight hours, an addition of three dB will expose you to 88 dB so the time of exposure will have to go down to four hours, 91dB sound levels, the equivalent of the sound produced by a jackhammer (electro-mechanical chisel and hammer) should be listened to for two hours, 94dB for one hour and so on. Above certain levels, damage could happen to the inner ear in seconds.

Ear pieces
If music is heard by another person next to the one wearing an ear piece, then the music is probably above 85 dB, which is too loud. MP3 players can produce from between 100-120dB of sound which is the equivalent of the sound level of a music concert. It is not advisable to listen to more than 60 per cent of the volume levels through your headsets.

To prevent ear damage, reducing the duration of playing music is good but the intensity of reduction is more important as you can see from the regulation of halving for every increase in 3dB. The impact of noise adds up over a lifetime. If you are exposed to loud sounds on a regular basis, your risk for permanent damage adds up as you age.

Identify and remove hearing loss risks

Your ears can be your warning system for potentially dangerous noises.
The noise is too loud when:
• You have to raise your voice to be understood by someone standing nearby.
• The noise hurts your ears.
• You develop a buzzing or ringing sound in your ears, even temporarily.
• You don’t hear as well as you normally do until several hours after you get away from the noise.
If you are around noises at this level, take protective action. To avoid hearing loss,
• Turn down the sound.
• Avoid the noise (walk away).
• Block the noise (wear earplugs or earmuffs)
• Opt to use noise cancellation headphones.
Noise cancellation headphones

Samuel Ayo, head of Device Service Huawei says that noise cancellation headphones can be a good option to protect your hearing.

These headphones can be used in turning up the volume to block out external noise and in turn help you to keep the volume down. “Headphones work to cut off and remove those unwanted sounds while preserving the original audio signal that means you can listen to music and sound from your phone at much lower volumes than you would have otherwise listened to,” Ayo explains.
Noise cancellation headphones can be bought online for between $150-$300 (Shs400,000- Shs800,000).

Protect your ears
Identify hazards. Know which noises can cause damage.
Take precautions. Wear ear plugs when you are involved in a loud activity that is 110 decibels and more. This is the equivalent of the jet engine sound.
Frequency and duration. Regular exposure of more than one minute to sound levels at 100 Decibels, the equivalent of a loud music concert or a power saw, risks permanent hearing loss.
Know your limits. No more than 15 minutes of unprotected exposure is recommended at 85 decibels, the sound of car traffic at a close distance.