Noise is weird. And just as science seems to catch up with new information regarding the effects of noise on humans, some new weird factor is called into play.
Most people today understand that noise can affect humans negatively, but not everyone realizes that harmful noise is not limited to those sounds that make everyone’s pulse race and ears hurt, like police and ambulance sirens racing through the streets, loud amps and speakers at heavy metal concerts, and the ear-piercing shriek of a NASCAR event. These sounds glean the same reactions from most caught in their path, and it’s rarely a good one.
But less in-your-face sounds can be just as troubling to our hearing and health as the obvious noise offenders listed above. A growing body of scientific evidence confirms that the chronic din of ambient construction noise, road repair projects, airline traffic and even neighborhood lawn equipment is chiseling away at our sensitivity to sounds every day, and the results are not good, even if we stopped noticing them.
Noise, defined as unwanted sound, is largely a matter of individual perception. For instance, the sound of car-rocking rap tunes blasting from a passing auto are going to get a different response from the vehicle’s passengers than the residents of the quiet residential street through which it’s passing at 11:00 at night. In fact, individual perception has made it difficult to provide scientific proof of the health effects of noise, since the reaction to many sounds is going to depend on sensitivity and personal perception.
Still, study after study has found that noise in communities is interrupting our sleep, interfering with our children's learning, suppressing our immune systems and even increasing our chances of having a heart attack.
And experts on the effects of noise on our health are quick to remind us that we should not have to tolerate living with noise.
Everyday noise is under the radar, yet it affects everyone's life. No one would agree to live with “just a little” sewage in their water, so why should anyone tolerate noise pollution coming into their ears?
For instance, when your neighbor uses a leaf blower in his yard, he may be generating a sound that is only a little less intense than the 85 decibels that the National Institute of Occupational Safety and Health (NIOSH) says is physically damaging over a period of hours, but still more than loud enough to make it almost impossible for anyone within earshot to concentrate.
Modern transportation -- cars, motorcycles, trains, trucks and air traffic -- accounts for most of the background noise that disturbs and even sickens people.
More than 40 percent of Americans whose homes have any traffic noise at all classify that noise as "bothersome," according to the 2005 American Housing Survey, conducted by the U.S. Census Bureau. One-third of those say the noise is so bothersome they want to move. All told, more than 100 million Americans are regularly exposed to noise levels in excess of the 55 decibels that federal agencies have deemed reasonable in background intensity.
One Dutch analysis combined the results from 43 studies that tracked chest pains, heart attacks and related problems with community noise levels. Using a statistical technique called meta-analysis, it concluded that there is "a slight increase in cardiovascular disease risk in populations exposed to air traffic and/or road traffic noise."
Even if chronic exposure to noise is unlikely to kill you, it can simmer under the surface and take a toll on your well-being.
Studies have shown that chronic night noise not only leaves you fatigued, irritable, and struggling to concentrate the next day, it also activates the stress response as you sleep. And while the number of awakenings per night may decrease as you adjust to the noise, increased heart rate, blood pressure and breathing changes persist.
In fact, the Environmental Protection Agency (EPA) has claimed that the idea that people get used to noise is a myth. Even when we think we have become accustomed to noise, biological changes still take place inside us.
High levels of mechanical noise, such as that from a hospital's own air-conditioning equipment, can delay recovery in patients -- a reflection of the immune suppression that comes with an activated stress response.
Another insidious effect of noise is its cultivation of what scientists call "learned helplessness." Children given puzzles in moderately noisy classrooms are not only more likely to fail to solve them but are also more likely to surrender early, according to a Cornell University study. The implications of learned helplessness on a child's success in life can be quite powerful.
Perhaps most disturbing in these times of political and economic polarization is that noise undermines generosity.
In one study, people were less likely to help someone pick up a bundle of dropped books when the noise of a lawn mower was present. Another showed that in a noisy environment, people playing a game were more likely to see their fellow players as disagreeable or threatening. Yet another found a decrease in helpful behavior when loud "annoying music" was played.
Interestingly, helpful behavior increased when similarly loud "uplifting music" was played.
Which brings us back to the weird thing about noise: its mysterious psychological component.
One of the most pervasive sources of noise pollution in suburban neighborhoods is lawn equipment. The Noise Pollution Clearinghouse (NPC), a nonprofit agency providing access to a variety of materials on controlling noise pollution, has chosen lawn equipment as one of its primary focuses.
“The average life of the lawn mowers and weed trimmers in the United States today is about seven years,” says NPC executive director Les Blomberg. “By 2011 most of today’s stock will be in the recycle heap. There is a tremendous opportunity to reshape our neighborhood soundscapes by reshaping the lawn and garden marketplace.”
According to data provided by the NPC’s annual “Quiet Lawns” report, which rates various brands of lawn mowers on noisiness, a typical two-stroke gas-powered lawn mower subjects the operator to 85–90 dBA and should be operated only while wearing hearing protection. The latest (2004 model year) gas mowers employ four-stroke engines producing as little as 82 dBA. Electric-powered lawn mowers are quieter still, with the best model emitting only 68 dBA and not requiring the use of hearing protection. For small, evenly contoured lawns, consumers may want to purchase an old-fashioned reel lawn mower, used by golf courses because of their better cut. Some models produce as little as 63 dBA.
The NPC will be adding ratings for weed trimmers and chain saws to its annual report. “Our motto is ‘good neighbors keep their noise to themselves,’” Blomberg says.
As awareness is raised about the effects of noise on human health and well-being, public demand for controlling that noise will increase. In the not-too-distant future, technologies for developing machines that generate excessive sound may also incorporate the technology to suppress it. For societies seeking to cope with sensory overload, devices and innovations to reduce the sounds of modern life—and thus noise pollution—are good news indeed.
Edward L. Sadowsky of Long Island City complains that officials have not muffled the fans in a building visible from his 39th floor apartment. Below: The fans seen from Sadowsdky's window.
In New York City, industrial fans that clean subway airspace when workers are making repairs are driving people to distraction – and sleepless nights. In fact, for some residents of Queens the noise from the fans makes sleep virtually impossible.
They have been in place for decades and sound like a giant rattle shaken at great speeds, unrelentingly and with no set pattern. One weekend they might run for just an hour, the next weekend for 24 hours straight. At a subsidized housing complex for the elderly that sits right next to the fans, the sound became so intense and lasted so long, people approached the building’s superintendent crying because the noise prevented them from sleeping.
The fans are necessary for maintenance crews to do their jobs. However, the sound that one neighbor compares to “a blender running at full speed on the pillow next to him,” and another to the roar of a jet engine just before takeoff, the potential for serious health effects is high. .
“I wear earplugs, I put a pillow over my head, but I still can hear it,” said Nancy Haitch, who lives on the 11th floor of the building, Citylights, the first residential high-rise built in what was once an industrial wasteland.
Area residents affected by the fan noise have lodged complaints through the city’s 311 system and with the Metropolitan Transportation Authority, but to no avail.
Transit officials say that it would cost $300,000 to muffle the noise, but that money would be hard to come by with the agency facing serious financial problems. The authority offered a reprieve last weekend: It instead turned on fans in Manhattan, on the eastern edge of Tudor City, according to a transit worker stationed by the fans in Queens.
“These are real people, and it’s real lives being affected,” said Councilman Jimmy Van Bramer, who represents the neighborhood affected by the fan noise and organized the meeting. “We’re talking about sleepless nights here, not just an inconvenience.”
Charles F. Seaton, a spokesman for New York City Transit, which operates the subway and bus service, could not say when the fans would come on during this period.
“I don’t have the schedule in front of me,” he said in an interview. Mr. Seaton added that while the agency has been considering a couple of alternatives to address the problem, “It would be a little bit premature to say what they are and how they would affect the fans’ noise.”
At Citylights — which has 42 floors and offers breathtaking views of the city — the noise has become the topic of conversation among neighbors who bump into one another in the lobby, in an elevator or at the lounge next door. And in some ways, it has brought them closer together. Mr. Christie, an office manager who has lived in the building since 1997 when it welcomed its first residents, said that though he welcomes the camaraderie, he is more concerned with how the noise might be affecting his health.
“I find myself going to bed at night wondering if the fans will come on and wake me up,” Mr. Christie, 44, said. “This unpredictability is psychologically draining, and after a while, it really gets to you.”
Excerpted from an article by By Fernanda Santos, New York Times
Initiatives to redevelop and renew previously blighted and/or densely populated urban areas are giving multifamily builders new opportunities for work, but many of these projects also involve heightened noise abatement issues that must be considered to avoid creating a building full of irritated tenants.
Nearby freeways, street-level construction and, most significantly, other neighbors can quickly turn a $500,000
luxury condo into a chamber of endless noise that results in homeowner lawsuits and expensive retrofits. To avoid this sort of cacophonic catastrophe, multifamily builders must be up to speed on the latest technologies, materials and noise-abatement Acoustiblok Products design standards before initiating new urban projects.
“It’s important builders recognize there is a noise problem in the first place. Noise is not usually a big concern for contractors because the ultimate goal is usually trying to build the building for a certain amount of money per square feet, when, in most cases, the tenant would happily pay more for a quieter living environment if they knew the option existed,” says Lahnie Johnson, president and founder of Acoustiblok Inc.
Since many of the available tracts of land targeted for urban residential development are in notoriously loud locations—near freeways, airports or industrial zones—the first thing to consider is usually the site itself.
“Orientation to things like highways or railroad tracks will dictate how acoustically resilient the exterior shell needs to be,” says Todd Beiler, principal with D. L. Adams Associates, an acoustical engineering firm with offices in Denver and Honolulu.
“Then you have to look at the structure of the walls and floor/ceiling spaces, and any sounds that may be generated by mechanical equipment like the air handling units or chillers.”
In relation to the building envelope, windows are the most critical noise-reduction element.
“Exterior walls are typically very well insulated, so windows are always the weak link for sound transmission from the outside. In that regard, laminated glass significantly out-performs standard glass when it comes to sound insulation,” says Beiler.
While site location and resilience of the structural envelope have a lot to do with minimizing a building’s sound levels, the biggest cause of noise complaints in most every multifamily structure —whether hotels, apartments or luxury condos—are the upstairs neighbors.
“The thing that causes the most headaches for building owners and residents is the floor and ceiling assembly. People tend to expect some noise from the street level or from mechanical systems, but noise from the upstairs neighbor is more annoying than anything else,” says Beiler.
Minimizing vertical noise transmission requires contractors to consider the complete floor assembly from top to bottom.
“Floor finish is one of the biggest factors for sound transmission. Obviously, stone and tile floors are the most challenging.
"Other things to consider include whether or not there is some sort of resilient or acoustical dampening layer underneath the floor, what the subfloor structure is, and how or if the ceiling is suspended,” says Beiler.
Designers of the recently finished Ko’olani, a 48-floor, 370-unit luxury condominium tower in Honolulu, spared no expense when it came to ensuring the comfort and privacy of residents. To
eliminate potential sound transmission from upstairs neighbors, the Ko’olani was built using Acoustiblok material as a subfloor soundproofing layer.
“Many architects will specify installation of noise-reduction barriers between units and floors only to have them value engineered out by thecontractor who may go with cheaper materials— such as extra layers of drywall. But noise-dampening products are superior because they use specialized polymers
that transform sound vibrations by turning them into inaudible friction energy,” says Johnson.
Advanced new materials are making it easier than ever for builders to eliminate sound problems between units and from outside. Keeping the communal peace can also be achieved using advanced soundproofing products from companies such as Soundproof Windows, a maker of secondary noise-eliminating windows perfect for remodel and post-occupancy situations.
Regardless, when building urban multifamily structures, a good rule of thumb is that, when given the option between “loud” and “not loud,” most people will be happy to pay a little more for “not loud."
Excerpted from "Sounds of Silence: Noise Abatement in Urban Multi-family Buildings," by Johnathon Allen, Builder News, September, 2009.
Sound that is undesirable for human hearing is called as noise. When there is a lot of noise in the environment, it constitutes what is known as noise pollution. Noise pollution can be caused due to various sources – there is street noise, traffic noise, noise in public transport places, noise in playgrounds and parks, noise in the shopping malls, noise in workplaces… the list is endless. One of the greatest sources of noise pollution is the airports, and anyone staying close to an airport will attest to that.
Sources of Noise Pollution
Sound is measured in a unit known as decibel. Though there is no fixed particular decibel limit to decide when sound becomes noise, it is understood that a continuously high decibel limit will constitute noise pollution. Some areas do designate their own sound limits, which of course vary from one legislation to another. In the United States, most states have a sound limit of 65 dB in the daytime and 55 dB in the nighttime, applicable to the streets. Anyone crossing this limit would be causing noise pollution.
However, all these designated sound limits are too ambiguous, because most appliances we use in factories as well in the household go much beyond the prescribed limits. The following are some of the sources of noise pollution that we are quite familiar with, but generally ignore:-
* Appliances in the home such as mixer grinders, vacuum cleaners, washing machines, etc. together cause a cumulative sound of about 87 dB. This itself is above the sound limits in most areas. On top of that, if loudspeakers, television sets and music systems are used with high volumes, then we can well imagine how much noise pollution is being created.
* Small factories using single unit machines would cause a sound of about 98 dB and above. The sound will definitely go higher as the number of machines increase.
* Airplanes cause the highest sound among all – 150 dB. But road vehicles are also great contributors of noise pollution. These vehicles include the trucks, buses, tractors, SUVs and even motorcycles and most cars.
* Then there are lots of environmental sources of noise pollution that cannot be ignored. Continuous noises are the most distressing. Noise coming from sources such as dripping taps and ticking of clocks can contribute to environmental noise pollution.
Effects of Noise Pollution on Health
Noise pollution can take a severe toll on human health in the long run. These effects will not become apparent immediately, but there could be repercussions later on. The following is a list of the kinds of effects noise pollution will have on human health after continuous exposure for months, and even years:-
* The most immediate effect is a deterioration of mental health. As an example, people who are living too close to airports will probably be quite jumpy. Continuous noise can create panic episodes in a person and can even increase frustration levels. Also, noise pollution is a big deterrent in focusing the mind to a particular task. Over time, the mind may just lose its capacity to concentrate on things.
* Another immediate effect of noise pollution is a deterioration of the ability to hear things clearly. Even on a short-term basis, noise pollution can cause temporary deafness. But if the noise pollution continues for a long period of time, there’s a danger that the person might go stone deaf.
* Noise pollution also takes a toll on the heart. It is observed that the rate at which heart pumps blood increases when there is a constant stimulus of noise pollution. This could lead to side-effects like elevated heartbeat frequencies, palpitations, breathlessness and the like, which may even culminate into seizures.
* Noise pollution can cause dilation in the pupils of the eye, which could interfere in ocular health in the later stages of life.
* Noise pollution is known to increase digestive spasms. This could be the precursor of chronic gastrointestinal problems.
Controlling Noise Pollution
Governments are making their efforts for controlling noise pollution, but we must appreciate the difficulty of the task. Unless and until we take care of ourselves, the problems of noise pollution will always loom large. Here are some ways in which we can make individual efforts at reducing noise pollution for ourselves and for others:-
* We must constantly check up on the appliances we use at home. Most of them have rubber insulation that act for sound proofing. But over time, this insulation may wear out, and that is when the noise pollution will begin. Keep track of which appliances need maintenance, and replace insulation if needed.
* Growing trees is a very significant way in which roadside noise can be curtailed. Trees act as buffers for absorbing the sound that is produced on the streets and hence reduce noise pollution. That is the reason why roads with trees on both sides seem to be more silent and peaceful. Grow trees around your house if you can. It will protect you from the noise on the streets. This will also help if you stay close to an airport.
* Do not honk horns in your vehicles unless it is absolutely necessary. We all know how easily traffic sound limits are trespassed when there is a traffic jam. We might be desperate to get through, but honking horns will not solve any issues. It will only add to the noise pollution.
* If you are working in a factory that has a lot of noise issues, make it a point to wear earplugs and muffs. If you are the owner of the factory, provide these things to your workers.
(Excerpted from an article by By Neil Valentine D’Silva)
Loud noise can have serious consequences to an individual’s health and well being. Elevated workplace or other noise can cause hearing impairment, hypertension, ischemic heart disease, stress-releated illnesses, premature ejaculation, sleep disturbance, decreased sexual performance and even death. Some experts suggest that changes in the immune system and birth defects have been attributed to noise exposure, although evidence is limited. Although some hearing loss may occur naturally with age, in many developed nations the cumulative impact of noise is sufficient to impair the hearing of a large portion of the population over the course of a lifetime. Exposure to loud noise has also been known to induce tinnitus, hypertension, vasoconstriction and other cardiovascular impacts. Beyond these effects, elevated noise levels can create stress, increase workplace accident rates, and stimulate aggression and other anti-social behaviors. The most significant culprits are vehicle and aircraft noise, prolonged exposure to loud music, and industrial noise.
The social costs of traffic noise in European countries and the U.S. is in the billions of dollars per year, with traffic noise alone is harming the health of one in every three people in some high-traffic communities. One in five individuals is regularly exposed to sound levels at night that could significantly damage health.
The location of site and noise generators near sites which are noisy include major roads, railroads, industrial plants, etc. Traffic maps and land use maps from highway departments, planning agencies, railroads, and airport authorities may document such noise generators.
Noise is also a detriment to animal habitats and ecosystems.
Acoustiblok’s all weather sound panels and other noise abatement products are helping industries and individuals combat noise-related problems every day. Acoustiblok’s sound absorption capability is more effective than a 12-inch poured concrete barrier.
Noise is defined simply as unwanted sound. Noise is perceived differently by every individual. A noise that is irritating to one person may be tolerable to another.
The smallest change in noise level that can be detected by the human ear is about 3 decibels.
A 10 decibel increase will cause the noise to be perceived as sounding twice as loud to the average listener.