Tips on how to avoid noise-induced hearing loss among youths

This series on common health concerns among youth was created in collaboration with Tan Tock Seng Hospital.

Hearing loss with increasing age is commonly experienced by the elderly. As such, the younger generation may think that hearing loss is something they only need to worry about later in life.

In reality, there are many different types of hearing loss, some of which can occur at any age. 

Hearing loss, which occurs suddenly, is always very obvious to the sufferer, but the onset of slow and gradual hearing loss often goes unnoticed for some time. Some types of hearing loss are unavoidable or out of the individual’s control, such as those due to genetic factors, infection, or the side effects of medicine which can damage the ear (ototoxic medication).

However, one type of hearing loss that is completely avoidable by the individual is noise-induced hearing loss (NIHL).

The World Health Organisation (WHO) estimated that over one million youths a year are at risk of NIHL, and a recent local study concluded that one in six Singaporean youths is at risk of getting NIHL.

Hearing health and hearing loss can be assessed by hearing tests. If hearing loss is found, the severity is categorised into mild, moderate, severe, and profound. 

Even moderate degrees of hearing loss can significantly impact your everyday life by interfering with interactions between family and friends and jeopardising your safety if you are unable to hear warning sounds or alarms.

Hearing loss which impairs your communication skills can limit your opportunities for education and employment. More severe hearing loss can even result in social isolation, affecting one’s mental health or leading to depression.

In the elderly, hearing loss is a known modifiable risk factor in the early onset and progression of dementia.

Loud noise can permanently damage nerves in the inner ear and cause permanent hearing loss. How quickly this occurs depends on how loud the noise is and whether the noise exposure is continuous.

For example, a loud explosion near the ear can instantly cause hearing loss. Continuous background noise, although not as loud as an explosion, may also cause permanent hearing damage over time.

An example of occupational noise is loud and noisy machinery at construction worksites, factories or airports. But even recreational noise can be loud enough to cause NIHL, such as the noise inside entertainment venues like rock concerts and discotheques. The loud volume of personal audio devices is also a common cause of NIHL.

A decibel (dB) is the unit used to measure the loudness of a sound. Any sound below 85dB in loudness is generally considered safe for hearing. For example, a conversation between two people normally takes place at about 60dB.

But above 85dB, a sound can potentially damage hearing — the louder the sound, the shorter time it takes for hearing loss to occur.

For example, the maximum period for safe listening at a noise level of 85dB is eight hours. However, the duration required to cause permanent damage is halved with every 3dB increment above 85dB. Therefore at a noise level of 100dB (e.g. chainsaw, loud rock concert), the maximum duration allowable is 15 minutes.

When in noisy environments, reducing the duration of loud sound exposure by taking listening breaks is highly recommended for safe listening.

NIHL can be avoided by observing these measures:

1. Limit your daily sound dosage by reducing volume and monitoring the duration of exposure 

Reducing the volume of sound is the most effective course of action for safe listening. As a rule of thumb, set the volume of your personal audio device to no more than 60 per cent of the maximum level. 

The amount of environmental noise can be measured using a sound level metre, and there are smartphone apps available to gauge the environmental noise level and help calculate your maximum allowable daily duration of exposure.

2. “Mute” or cancel background noise

Recent advancements in earphone and headphone technology provide active noise cancellation features which can decrease background noise, allowing you to listen at a lower audio volume.

3. Distance yourself from noise

Distancing or moving away from the source of sound always helps to reduce loudness. The loudness is halved when the distance from the sound sources is doubled. 

Choose a safe-listening spot if you are attending a concert or event. A quieter location is always a healthier choice to protect your inner ear hair cells. 

4. Using hearing protection

If work requires you to remain in an area of loud noise intensity (e.g. weapons firing range, airport runway, engine room, etc.), use hearing protection such as earplugs or earmuffs to reduce the amount of noise transmitted to your ears.

Taking preventative measures is the best way to safeguard your hearing.

But what if you are already having trouble hearing conversation or everyday environmental sounds, always having to raise your voice when talking, and asking others to repeat or speak slowly? 

In that case, it may be advisable to seek an audiologist or ENT doctor for a proper hearing assessment, as early detection is key to effective hearing rehabilitation. 

The World Health Organisation continuously promotes awareness about hearing loss and commemorates a World Hearing Day (WHD) in March every year.

This year, the theme for World Hearing Day 2022 is “To Listen for Life, Listen with Care” to emphasise the importance of safe listening. Find out more about your hearing health from Tan Tock Seng Hospital’s team of hearing experts at their WHD live webinar, or follow the TTSH Facebook Page for more hearing tips.

Ms Ng Poh Juan is a Clinical Audiologist at the Department of Otorhinolaryngology (Ear, Nose, Throat), Tan Tock Seng Hospital.