Protecting infants and children’s hearing 

Noise causes hearing loss in children and adults

In childhood, good hearing is important for speech and language acquisition, spoken communication, social and cognitive development, mental health, and educational success. In adulthood, hearing loss is associated, probably causally, with increased rates of falls, accidents, social isolation, depression, dementia, and death. Here, we review the growth and maturation of the human auditory system and discuss why children are more susceptible than adults to auditory damage from noise. We also offer recommendations about protecting infants’ and children’s hearing from noise, in the hope of stimulating greater concern, research and publication about this underrecognized topic.

When to check your child’s hearing

Your child’s hearing should be checked if you observe any of the following:

• Listens to the TV or radio at higher volumes than other children
• Sits closer to the TV when the volume is fine for others
• Asks to have instructions repeated
• Is easily distracted or bothered by background noise
• Has difficulty telling sounds apart
• Has trouble paying attention
• Experiences speech and language, school and learning, or behavioural problems
• Complains of difficulty hearing or blocked ears
• Responds inappropriately to questions
• Watches others to copy what they are doing
• People have to raise their voice to get your child’s attention
• Shows inconsistent response to sound
• Watches the speaker’s face closely to figure out what the person is saying
• Turns their head to face the sound source
• Talks in a soft or loud voice

Growing ears of babies and toddlers are susceptible to damage. Ears and hearing develop significantly in the first few years after birth. Providing hearing protection, especially at a young age, helps to ensure optimal hearing as your child grows.

Loud Sounds Are Even Louder for Kids

Infants and young children are more sensitive to loud noises than adults are. Because the ear canal is smaller in children, the sound pressure that is generated in the ears is greater compared to adults. In other words, loud sounds are even louder for kids.

How Loud is Too Loud?

Hearing damage due to noise exposure is permanent and cumulative. It is important to monitor your child’s surroundings for noise exposure that exceeds recommended levels. Sounds are measured in decibels (dB). Safe sound levels vary based on the duration exposure. In general, noises softer than 80 dB will not damage hearing unless the exposure lasts for several hours.

The facts about hearing:

• Sounds that are less than 80 decibels are unlikely to cause hearing loss.
• Hearing loss occurs when the tiny hair cells in the inner ear are damaged by loud sounds. Consistent exposure to moderate-level loud sounds (i.e., more than 80 decibels) damages the hair cells in the inner ear. Over time these cells die and permanent hearing loss occurs.
• Brief exposures to extremely loud sounds can cause permanent damage.
• If you have to shout to be heard, then you should avoid the situation or use ear protection.
• Personal listening devices (e.g., iPods®) can reach a maximum of 115 decibels, which is loud enough to cause permanent hearing loss with prolonged use.

Everyday sounds can affect your child’s hearing

Normal levels

• Whispered voice – 35 decibels
• Normal conversation – 60 decibels

Very loud levels

• Vacuum cleaner/ hair dryer/blender – 70 decibels
• Alarm clock or city street traffic – 80 decibels
• White Noise Sleep Machines- The amount of time an infant is exposed to sound is important. If you’re using an infant sleep machine, test the sound output before leaving it in a room with a sleeping child, and use the lowest volume setting possible. Additionally, parents should place the machine as far from the baby’s crib or bed as possible.

Extremely loud levels

• Restaurants – 90 decibels
• Noisy toys, lawn mower, shop tools, truck traffic, or subway – 90 decibels.
  Noise-making toys are popular. Some of these toys can produce sounds in excess of 120 dB. If possible, listen to toys before purchasing to see if the sounds are too loud. Remove the batteries from toys with excessive noise levels. Because children play with toys much closer to their faces and ears, even sounds in the 80-90 dB range can be damaging.
• Motorcycle – 95 decibels
• Snowmobile, chain saw, pneumatic drill, fireworks display or night clubs – 100 decibels
• Helicopter – 105 decibels
• Personal listening devices like portable music players used at maximum levels – 115 decibels

Dangerously loud levels

• Amplified rock music, band practice, car stereo, ambulance siren, jet plane take-off, motorcycles, or firecrackers – 120 decibels
• Jackhammer – 130 decibels
• Firearms or jet engine – 140 decibels
• Rock music peak – 150 decibels

Unsafe levels of exposure

• Very loud – 85 decibels. Prolonged exposure to any noise above 80 to85 decibels can cause gradual hearing loss
• Extremely loud – 100 decibels. No more than 15 minutes of unprotected exposure is recommended.
• Dangerously loud – 110+ decibels. Regular exposure of more than one-minute risks permanent hearing loss.

WHAT PARENTS SHOULD KNOW

Total auditory damage is the sum of all noise exposures, meaning noise-induced auditory damage is cumulative from birth to death. Children and adolescents are exposed to harmful noise from many sources, including toys, personal listening devices, band practice, movies, concerts, sports events, air shows, auto races, and life cycle celebrations. Hearing loss is common among the young. Tinnitus, a marker of auditory damage that can be found by asking, “Do you ever have ringing in your ears?” has been reported in 45%-92% of adolescents. Auditory damage has been detected in personal listening device users as young as 9-11 years.

Additionally, noise exposures at levels not thought loud enough to damage hearing can affect sleep and learning, may affect brain development, and cause auditory processing disorders. Excessive environmental noise affects poor and minority communities disproportionately.

Hearing loss in children can be prevented through:

• Providing newborn and infant hearing screening to identify and treat chiildren with congenital or early-onset hearing loss.
• Regulating use of ototoxic medicines to minimize dangers posed by their indiscrimate use. And regular audiological monitoring to be provided to help identify hearing loss at an early stage where the use of such medicines is unavoidable.
• Regulate and monitor noise pollution levels in the community, especially at recreational venues and sports areanas where children or infants will frequent.
• Raising awareness on healthy ear care practices to reduce ear infections.
• Raising awareness on dangers of loud sounds by educating children at an early age on the risks associated with high volumes.
• Provide hearing protection (such as ear muffs) for the child when the environmental noise is noisy or there is a likelihood in exposing the child to loud recreational environment.

WHAT PARENTS CAN DO

Parents may not think that loud noise is a hazardous exposure, but it is. If a noise sounds loud to an adult, it is likely too loud for a child. If one must strain to speak or be heard while carrying on a normal conversation at a normal social distance, approximately one meter, the ambient noise is above 75 dBA and the child’s hearing is at risk. Parents can turn down the volume, have the child use hearing protection, or leave the noisy environment. Noisy toys and popping balloons should be avoided.

Ideally, parents should not bring infants and children to noisy events. If it is not possible to avoid noisy events or places, parents can use earmuff-style hearing protection devices for their children, although these devices have not been rated for noise reduction. Earmuff cups should seal around the ears, snugly against the head. Parents should never stretch out the headband or otherwise modify earmuffs since that destroys the effectiveness of hearing protection.

Children older than toddlers may be able to use earplugs, with adult assistance if needed; earplugs may pose a choking hazard for younger children. Small size adult hearing protection earmuffs may fit older children. For occasional intermittent noise, parents can teach children to stick their index fingers into their external auditory canals. Personal experience indicates that merely cupping hands over the pinna does not attenuate sound sufficiently.

Watching videos on tablet devices or cellphones is a major source of noise exposure for children.

Following the American Academy of Pediatrics (AAP) screen time recommendations—none until 18-24 months except for video calls, and then no more than one hour a day between the ages of 2 and 5 years—30 may help limit noise exposure from personal audio systems. The AAP recommends that parents of older children address the type and duration of media use and set appropriate limits for each child.

For headphone use, or earbud use for older children and adolescents,

parents can purchase those with noise-canceling or sound isolating features that permit lower listening volumes in noisy environments; turn on device settings and safer listening features to the lowest intensity sound exposure possible; and lock the settings under parental controls. Volume-limiting headphones are safer than those with no volume limit, but they are not necessarily safe for hearing. Parental controls, volume limits, and safer listening features are often easily overridden by children.

NR Rating

NR Rating (NRR) defines the effectiveness of the noise canceling feature of the ear protective wear. However, not all rating provided for the ear plugs or ear muffs are accurate as the measurement and ratings are given in labs, where the conditions differ from on manufacturer to another. Buying from an established brand is therefore much more important than solely relying on the rating provided. As a rule of thumb, the higher the ratings, the better the protection.

Parents can teach older children and adolescents the importance of safer personal listening to protect hearing.

This includes listening at the lowest comfortable volume below 50%. If systems alert the user about unsafe loud personal listening, children should heed the warning and turn down the volume. Parents can also model safer listening practices for their children.Parents and grandparents can advocate for quiet and for hearing protection use at schools, school boards, and city or town councils. Specific actions to protect children’s hearing in school include making sure that classrooms meet recommended acoustic standards; purchase of safer volume-limiting headphones for classroom use; and requiring hearing protection for band and orchestra practice and in shop classes. Noise limits for children’s movies, restaurants, and concert venues will protect both children’s and adults’ hearing.

Noise-induced hearing loss is insidious, irreversible and like many adult conditions and diseases—obesity, diabetes, and hypertension among them—starts in childhood. Infants, children, and adolescents are especially vulnerable to the many adverse effects of excessive noise. Parents can take steps to protect children’s hearing, which must last a lifetime. Additionally, professional organizations and public health authorities must pay greater attention to noise exposure risks for the public.