Todays world is truly a marvel of its own. We have made extraordinary advances in technology, transportation, education and engineering, but with all the advantages that come with these advancements in the modern world, disadvantages come with it also. We have become well informed about diseases, psychological, and health. Along with this came tons of research on how to be healthier, how to eat correctly and how to take preventative measure to ensure that you do not get sick, we have gone to extreme lengths to help fix and prevent vision lost. So as you can see todays modern society has pretty much covered everything, well not quite yet.
Its sad to say but society has over looked sound. Sound is all around us all day and all night, even when we think its completely quite it actually is not. Our hearing is something that we take for granted in our day to day lives, but there is something not many people know and that is your hearing does not come back. Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations. The American Heritage Dictionary of the English Language, Fourth Edition] So when comes down to it, all sound is is tons of molecules wether being gas, liquid or solid that collide together in a wave formation. But what transforms that energy into “sound” as we perceive it, this is where the ear comes in. The ear can be divided into three main parts: the outer ear (Pinna), the middle ear and the inner ear. The outer ear is responsible for helping us locate the original location of the sound, like if its above, bellow, behind or in front of us. It also helps to funnel and focus sound waves on their way to the middle ear.
The middle ear contains the auditory canal, which ends at the eardrum, or tympanic membrane. Attached to the other side of the eardrum, in a small air pocket, are three tiny bones which make up the ossicles. These three bones are called the malleus, incus and stapes, these bones are attached to a fluid-filled structure called the cochlea in the inner ear at a point called the oval window. Here the vibrations transmitted from the eardrum through the tiny bones are converted into electrical impulses sent along the auditory nerve to the brain. [How does the ear work? But what does the ear do to help protect itself? Our ears have a built-in defense system to protect themselves against loud noises. In the middle ear there are two muscles that contract when loud sounds occur that could possibly injure the inner ear and cause some loss of hearing. The first muscle contracts to decrease the vibration of the eardrum when noise exceeds a certain level. The other muscle cuts down on the movement of the stirrup bone in the middle ear. This helps reduce the severity of the vibrations that are transferred to the fluid of the inner ear.
All this is to help protect the delicate structures In the inner ear. This is the ears only defense against damage, and it was developed (evolved) 85 million years ago with chimps. The loudest noises this was used to protect from was most likely thunder, it was not created to protect against the constant loud abuse. There is a very delicate but vital organ that is in the inner ear and that is the Corti. This is where vibrations are converted from mechanical energy to electrical impulses that travel up the auditory nerve to the hearing area of the brain.
The Corti organ is what gets damaged and leads to loss of hearing. The Corti organ is a sensitive element within the inner ear, it contains four rows of hair cells which stand on the surface. Above the hairs is the Tectoral membrane which can move in response to the pressure changes from the fluid. There are some where between 16,000-20,000 hair cells along the basilar membrane. The hairs are what gives us the perception of pitch, different hairs start to vibrate at different frequencies. The louder the source the more violently the vibrate causing them to become warn out and or damaged.
Right when you are born these hairs start to become warn out and brake, the higher frequency ones are the most fragile. Quick exposures to loud sounds usually does not cause any damage or severe damage, but long expose to loud sounds can severely damage them, once they get damaged they do not heal or grow back. The pain threshold for the human ear is 130-140 Decibels, just to show some sound levels of stuff around you the normal conversation level is between 60-70dB, a busy street is 70-80dB, inside a bus (not including talking) is 80-90dB, inside a subway train 90-110dB and a ar horn 110-120dB. Now that we know how sound get into our minds how does the noise effect us. [noise pollution] One case that we all have known for a while is how sound Impairs our ability to do work. All these sounds can impair our performance at school and at work, increasing errors, and decreasing motivation. A study was conducted and it showed that the leading reason why students didn’t do good work was because they did homework in loud environments. Now that is a given to us all, that loud noises distract us, but what if it effected our mood?
A study in The Mediation of Aggressive Behavior show that when noise levels are at or above 80 dB that its found that there is both an increase in aggressive behavior and a decrease in behavior helpful to others. One of the most widely known effects is sleep disturbance these can be caused by sounds as low as 45dB, thats as loud as a refrigerator, some studies show that at these quit of levels people start to have trouble sleeping. In urban environments the number one cause of noise pollution is cars, now lets do some math here.
According to the United States Census Bureau the average population of a suburb is about 1,860 and the average family size is 3. 2, we will just say its 3 because that . 2 person most likely isn’t driving anywhere soon. [Illinois QuickFacts from the US Census Bureau. ] That mean that in the average suburb there is 620 families. Now if both parents work they will have two cars, this means that there are 1,240 cars in the average suburb. The average dB level inside a car is 85dB, can you imagine what it would be on the outside. Decibel (Loudness) Comparison Chart] Now a lot of the sound is lost in the somewhat open environment of the suburb but ill leave you with this to think about, In the city of chicago the sounds from cars cant escape it bounces off the building and right back there is a population of 2,851,268 and on average about 80,000 commuters, how many cars is that?
One question I still have to answer is how the environment around us has changed over the years. If you think about it in the 21st century we live in a much loud environment. When we first came crawling out of the trees nearly 4,000,000 years ago the loudest sounds around us were trees falling nd thunder occasionally. Our ears were evolved to withstand that kind of noise level. If I had to guess it probably was not until the Industrial revolution the really started to live in a very loud environment. But after some research evidences shows that societies were worried about noise all the way back to the romans. In Roman times evidence shows that at night chariots and or any thing that involved a wheel to help it move was banded from the streets because the wheels would clatter on the paved stone streets. This was instituted to prevent the noise from disrupting the sleep of the near by citizens.
This idea was used Centuries later in Medieval Europe. What they would do was like Rome banned horses and or horse drawn carriages from the streets at night in order to help control the noise at night for people to sleep. After a while they discovered that laying down hay on the street help dampen the sound allowing the horses and horse drawn carriages to travel at night allowing the residents to have a peaceful sleep. In the 1780s the framers of our constitution laid down earth above the cobblestone streets in order to prevent noise induced interruptions.
This also can show that even in the 1780s the effects of noise on work and sleep were recognized. [Environmental Protection Agency] If you live in the city of chicago and than visited a suburb of chicago have you ever noticed how quit it is. To us it seems very quite but to the people who live there the very same atmosphere could be very loud to them. Its all about what we are use to and what type of noise pollution we live in. So you could possible say that we created this whole “noise having physiological effects on us problem”.
To those city dwellers folks noise pollution is continuing to grow, It was estimated that in the 1980s there was a 10% increase in the noise across the united states. [Gershon RR, Urban Health] In the European Common Market 65% of the population was and still is being exposed to unhealthy levels of transportation noise. Maximum noise levels on a New York City subway platform can reach up to 106 dB and inside a subway car up to 112dB, both these levels exceed the recommended exposure limits and can cause serious hearing damage. [Gershon RR, Urban Health] In a 2000 Census conducted by the United States 30% of Americans complain about the oise level and 11% found it to be bothering. Of those who complained 40% of the people were bothered enough by the noise that they wanted to move. [U. S. Census Bureau] But this raises a question, why are we so tolerable about this? Its a well known fact now that loud noise are hurting us, but we just accept the fact that it does. When in the city you can see just a hand few Maybe even less that plug there ears when emergency sirens go by. But now parents go to very far lengths to protect their children’s from dangers of the outside world, but a very minuscule amount go to lengths to protect their children’s hearing.
Hearing is one thing you can not fix, from the moment you are born you start to loose your hearing. And we have figured out no way to repair our hearing. So we are abusing a part of our body that we have no way of repairing. And for what? What are we getting out of destroying our hear? Nothing. The only thing we are getting is being able to listen to loud music out of our headphones, 80% of elementary school children use personal music players, many of them use them for an extended period of time and at potentially dangerous volume levels. [McCale] In 2001, it was found out that 12. % of children in america between the ages of 6 to 19 years of age had impaired hearing in one or both ears. [Niskar AS, The third national health and nutritional examination survey] Thats all well and good but by the time you are thirty you will have been exposed to large and will have a very loud ringing in your ear for the rest of your life and you wont be able to hear anything. Some babies are being diagnosed with tinnitus at the age of 3 [Berglund B].
About 5% of all children the ages of 18 years and younger have been diagnosed with hearing loss. Hearing Loss in Children] There has been many test on how hearing loss, not complete hearing loss, effects the development of a child. The largest effect being the delay in the development of receptive and expressive communication skills. [American Speech-Language-Hearing Association] So you would think that after seeing how it can effect a child’s life that parents and adults would be more carful also. A recent survey was conducted and most young adult responded saying that they were experiencing tinnitus or impaired hearing after going to many loud concerts and clubs.
Only 8% considered loosing there hearing a significant problem. Many others responded saying that they would be more motivated to use ear protection if they were aware of the potential dangers. [ Niskar AS, The third national health and nutritional examination survey] Noise pollution has always been around but it became more and more a problem during the industrial revolution. Between 1987 and 1997 noise levels in communities had shown that there was a noise level increase by 11percent. [Staples, Susan] In 1972 the Congress passed the Noise Control Act, stating that “… t is the policy of the United States to promote an environment for all Americans free from noise the jeopardizes health and welfare. ”
What they did was start to set standards for noise emissions and also authorized federal agencies to establish rules. [Pollution, Noise] soon after this the EPA created an Office of Noise Abatement and Control (ONAC) as a result of The Noise Control Act. In 1978 the Quiet Communities Act gave authorization to the EPA to provide grants to states and local government noise abatement. Pollution, Noise] In the 1980s the Occupational Safety and Health Administration (OSHA) set standards for industrial noise exposure and created criteria for hearing protection. [Stellman] In 1982 and the Office of Noise Abatement and Control closed. [Environmental Protection Agency] With studies showing us how sound and sound pollution can effect ourselves and our lives, is there possibly a way that we could use this to our advantage? Scientists and weapon designers are, these are called Sonic and SuperSonic Weapons.
These weapons use extreme high power sound waves which can disrupt and/or destroy the eardrums of the targets, they can also cause severe pain or disorientation. These weapons were originally designed as a non lethal weapon to control riots. Sonic weapons can use one larger speaker and thousands of micro speakers in the shape of a bigger speaker. The bigger the speaker (woofer) the more directional it becomes (beam like) so you have more control over where sound goes [Yenigun], but a bigger speaker cant possibly recreate the higher frequencies.
What they came up with was thousands of smaller speakers that move in sync with each other, this gives them the advantages of a larger speaker (directionality) and the advantages to smaller speakers (frequency). But you don’t always want higher frequencies, It is proven that although higher frequencies can incapacitate a person, less power (lower frequency) can cause nausea and discomfort. [Yenigun] These weapons can be so effect without causing serious injury to humans, the worst case scenario being popping the ear drum.
Everything that I have mention is only a small amount about what is truly going on with the damage our ear get bombarded with on a daily basis. You can not stop it from happening it will happen no matter the action you do but you can slow it down and all you have to do to help prevent it is carry a little pair of foam ear plugs with you. When you get onto the L Train just put them in, its thats simple and keeping your hearing is a wonderful reward. Its really up to you on how long your hearing lasts and no one else’s. This issue about noise pollution is never going to go away and as we become more and more populated it will only get worse.