Protecting Your Hearing

What is noise?

Noise can be defined as any unwanted sound that when loud enough, can damage your hearing permanently. Noise can range from a shotgun blast to recreational music that you would listen to at home or in your car. There is a general trade off between the loudness and the length of time exposed to the noise. The louder the sound, the shorter the time you should be around that noise before it causes damage.

Aside from destroying your hearing, noise can be a source of tinnitus, fatigue, annoyance, stress, and can interfere with communication. Tinnitus is often perceived as a high pitched ringing or buzzing that can become constant and permanent.

Can music damage hearing?

Any sound, if loud enough, can damage your hearing. Whether you are a fan of easy-listening, hard-rock, or classical any music played loud enough can harm your hearing permanently. Other everyday sounds such as noisy toys, lawnmowers, and televisions or those sounds associated with certain workplaces such as factories or construction sites can also contribute to hearing damage. All sounds have the potential to have a permanent effect on hearing if not properly controlled.

Can one exposure to a loud sound harm your ears forever?

There are three types of noise-related hearing loss. Temporary damage is done slowly and will often come back after a rest from the noise. Often people who have attended a loud rock concert have experienced this type of hearing loss.

Permanent hearing loss occurs over time if the noise/music is loud enough and the exposure time is long enough. The damage sustained is cumulative, so each new exposure can add to hearing loss. Finally, there can be a sudden permanent hearing loss if there is exposure to a brief but very intense sound.

How loud is too loud?

Sound is measured in units called decibels (dB). While there are laws guiding the amount of noise a person can be exposed to in the workplace, noise is considered too loud if the sound is over 85 dB. To put noise in context the wind in the trees can be 20 dB; a person when talking can be 55 dB; a chainsaw can be measured at 95 dB; and a single handgun blast can be as much as 160 dB.

As a rule of thumb, if you have to raise your voice over the noise, you should be wearing hearing protection. No person should be exposed to sounds over 120 dB for even very short periods of time without hearing protection. Levels over 120 dB can cause permanent damage even after one brief exposure.

How can I tell if I’ve been exposed to loud sounds?

Generally, after a loud exposure to sound you may feel as if your hearing is dulled, your ears may seem full and/or you may get tinnitus.

How can I protect myself from noise?

The best protection is to avoid exposure to any loud sounds. If that is not an option, wear some form of hearing protection such as earplugs or earmuffs. Under the law, any person exposed to noise over a certain level on the job must have hearing protection available on site. Companies which follow these laws have noise programs that monitor the noise and conduct annual hearing tests on all employees who are routinely exposed to noise.

At home you should have a set of earplugs in your workshop or carry a set of earplugs in your jacket. If you can control the loudness or volume of the noise, your best approach is to turn down the volume.

What about playing music on my car stereo?

Most certainly the noise levels obtained from most car stereos can reach levels which are damaging to your hearing, especially with the windows up. Some high end car stereos can reach levels which exceed 130-160 dB. Even short exposures can permanently damage your hearing.

The best advice is to turn the volume down. Once your hearing is damaged or you develop constant tinnitus it cannot be repaired. The best action is prevention.

Is it safe to listen to earphones?

Sony Walkmans™ first came to the attention of the public in the early 1980s and we have had portable music ever since. The 1990s saw the introduction of portable CD players, and more recently MP3 players such as the iPod™ have become available. It is tempting to wonder whether listening to music with earphones is dangerous, but this is actually not the problem. The listener will always adjust the volume of their music to a comfortable listening level, and the ear does not know whether the music came from a radio loudspeaker or an earphone. There are subtle differences between loudspeakers and earphones, but nothing significant.

The issue is one of “portability”. Whenever there is background noise, we prefer sound (such as speech and music) to be louder. This is called the Lombard Effect, also known as the cocktail party effect. Because of technical advancements we can now take music with us onto the subway, in our cars, when jogging beside a noisy road, and to the gym. Once there is traffic noise or other background environmental sound, the volume is turned up. When we are in environments with background noise, we tend to turn up the volume to unsafe levels. It is these unsafe levels, combined with the duration (or how long we listen to the music) that will determine safe and unsafe levels.

Most young people will agree that music needs to be loud, but the trick is that this loud music does not need to be intense. Huh? Although related, loudness and intensity are actually two different things.

Intensity relates to the physical vibration in the air and can be measured with a sound level meter, usually in a unit called a decibel (dB). Loudness is merely our subjective feeling about the intensity. While we use loudness to set the volume control of the MP3 player, it is the intensity of the music that causes hearing loss. There is no such thing as a “loudness meter” – loudness is a very individual thing.

We know from years of research that any sound over 85 decibels can eventually cause hearing loss. It is quite amazing how quiet 85 decibels really is – a dial tone on a phone is 85 decibels. A potentially damaging noise or music level actually does not sound loud. However, it is not only the intensity (in decibels) but also how long we listen to the music. It turns out that 85 decibels for 40 hours each week is the same as 88 decibels for only 20 hours; 91 decibels for 10 hours; 94 decibels for only 5 hours; and so on. While we don’t listen to music for 40 hours a week, many of us do listen for 5 or 6 hours (while on the subway or gym, for example).

Here is a guideline derived from recent research by Dr. Brian Fligor of Harvard University: It is safe to listen to 120 minutes of music at 60% of the volume. This is called the 120/60 rule and will provide the listener with half of their daily dose of music – you can still mow the lawn, and do other noisy things throughout the day. Moderation is also important; if your favourite song comes on, turn up the volume; just turn it back down to 60% or lower, when the song ends.

How can I protect my hearing at home?

Help protect your tween’s hearing for a lifetime. Teach him or her about the sources of excessive noise in and around your house that can lead to noise-induced hearing loss (NIHL), and how to help keep it down. Every day, we hear a variety of sounds in our homes. These sounds range from the gentle hum of a refrigerator to a blaring fire engine passing by. Most household sounds are at safe noise levels. Sometimes, however, we operate several noisy devices at the same time or raise the volume on the television so that we can hear it over the vacuum cleaner. When we take these actions, we raise the overall noise level in our homes without even realizing it. Noises in our homes can reach a level that is uncomfortable or even harmful to our hearing. Some common devices, such as power lawn mowers, are noisy enough that hearing protectors are recommended for even short exposures. Make your home a peaceful place. The result will be good for your hearing and your health!

Tips for creating a quiet home You can create a quiet home in three ways:

  • Reduce noises at the source.
  • Avoid competing noises in the same area.
  • Make your family aware of noise sources, noise levels, and how to avoid unsafe noise levels.

Here are some practical tips for creating a quiet home:

  • Set your television, video games, and music to the lowest volume at which they can be heard clearly.
  • If someone in the room has trouble hearing, consider turning on your television captioning rather than turning up the volume.
  • Create ways to muffle the noise of chores. An example is to close the door between family members and appliances in use, such as those in a workshop or laundry room.
  • Buy quiet toys. If you buy electronic toys, choose those with volume controls, and use only the lowest volume setting. This will both lower your household noise levels and help protect your child from NIHL.
  • When buying certain appliances, such as a fan, range hood, or dishwasher, ask about its noise rating. Some ratings are given in “sones”: the lower the sone number, the quieter the unit.
  • If your home is in a particularly noisy location, work to keep outdoor noises outdoors. Caulk cracks around windows and doors. Insert putty or expanding foam around pipes and wires where they enter the house.
  • Close windows and doors against potentially harmful sounds, such as leaf blowers, lawn mowers, power tools, and sirens.
  • Use soft furnishings to soften noise indoors. The more cushions, curtains, and wall coverings you have, the more noise will be absorbed.
  • Place carpets and area rugs over hard flooring to help soak up sound. Thicker rugs are more effective at reducing noises that bounce off of hard surfaces.

By taking just a few simple steps, you can achieve a home that is filled with only safe, peaceful sounds.

Can Natural Supplements Prevent or Help Hearing Loss?

It has recently been discovered that certain pharmaceutical drugs can reduce the damage to the ear caused by loud noise; this has to do with altering the metabolic by-products of cells. When a person is subjected to loud noise or music, the metabolism of the cells in the inner ear increases and generates a form of oxygen that contains free radicals. This is called Reactive Oxygen Species or ROS. This can be quite toxic to the structures of the inner ear. One strategy that appears to offer some relief is to use “antioxidants” that serve to mop up the toxic oxygen molecules and thereby preserve hearing.

In some research studies using animals the antioxidant is injected directly into the inner ear. However this is understandably not clinically feasible for humans. Other research has looked at antioxidant medication taken orally which is then absorbed by the entire body, in hopes that some of it will find its way to the inner ear. One such antioxidant is called L-N-acetyl-L-cystine, or more simply “L-NAC” and may be found as an ingredient in over the counter supplements sold in health food stores. Early results of an oral antioxidant (such as L-NAC) appears quite promising. However it should not be considered a cure for inner ear hearing loss or to be used as a substitute for hearing protection or other methods to minimize exposure to loud noise. L-NAC has been used for years in hospital emergency departments to treat Tylenol overdose that can be quite toxic to the liver.

There are a few other pharmaceutical routes being investigated such as medications that prevent inner ear cell death (prevention of apoptosis or necrosis) from loud noise, however the research is still in the early phases and none of these approaches have received approval from the Food and Drug Administration (FDA) in the United States or through Health Canada.

Consumers should be cautious when it comes to seemingly outrageous advertising claims on the labels of uncontrolled pharmaceuticals. Claims such as “Will cure ringing in the ears” or “will prevent hearing loss” is simply not substantiated by the research literature.

What can I do if I suspect a hearing loss, if I develop tinnitus, or I have any questions about hearing and noise?

If you suspect that you have a hearing loss, or if you have tinnitus, consult an audiologist or family physician. An audiologist is a professional who is trained to test your hearing and give you advice about hearing loss or tinnitus as well as give advice on prevention of hearing loss, especially from noise exposure.