Commentary: The sounds around us | Soundproofing with Dave

5.09.2011

Commentary: The sounds around us



One of my greatest pleasures, and one of the most soothing in these days of relentless stress, is listening to the sound of the sea.

One of my greatest pleasures, and one of the most soothing in these days of relentless stress, is listening to the sound of the sea.

It doesn’t matter whether it’s the pounding of waves during a winter storm or the soft susurrations of more gentle surf, the sound can smooth away all my anxieties. It’s one of the reasons we continue to live on these Islands.

It’s easy to imagine the way things were here 100 years ago: almost no man-made sounds at all. Maybe somebody hammering a boat together, chopping bush or digging their ground. Maybe even the occasional Saturday night kitchen band (unamplified, of course).

But there were no machines, no television, CD players or boom-boxes, and no vehicles except horse-drawn carts. Think of it – no jets, no trucks (no Jake brakes), no cars, no leaf-blowers, no outboards, no Jet-Skis, no bulldozers, no nightclubs, no DJs, no fireworks, no telephones, no air conditioners, no generators.

It was QUIET!




Instead, there were the sounds of nature. In addition to the ever-changing symphony of the sea, there were the birds, the wind in the trees, the buzzing of insects. Crabs and lizards rustled the leaves, and you might even hear a crocodile roar. Oh yes, and, of course, the perpetual whine of those pesky mosquitoes.

It was easier to sleep in those days (as long as you could keep the mosquitoes out!). The sounds that surrounded our not-so-distant ancestors were those to which our bodies and minds had adjusted over many millennia.

We were “in tune” with our surrounding environment in ways we can only imagine today.

As the last half of the last century progressed – and I use that term loosely – our society steadily acquired the trappings of modernity, and with it came the noises which accompany such a society.

Layer upon layer of man-made sounds crashed against our consciousness until we have reached a point where the noise that assaults us every day has begun to have profound effects on our psyches.

So noise is irritating. But it isn’t really harmful – is it? Well, animals change their migration routes to avoid noise, and military sonar disturbs marine animals like dolphins and whales. Why should we be any different?

150 decibels ruptures eardrums

Our ears are a finely tuned mechanism that can catch weak sounds at zero decibels (the unit by which we measure noise) in a quiet environment. But when the volume starts rising, the ears rebel.

At 120 decibels ears register pain, and sounds measuring 150 decibels can rupture the eardrum. But the damage may start much earlier, at 90 decibels. Noise pollution may also cause irritability, indigestion, high blood pressure and even heart disease.

There has been much scientific and accompanying psychological study carried out on the impacts on us of noise – of both everyday and excessive sounds. None of the results are particularly good, but we still tend to go our merry way and put up with the racket. And the decibels keep getting higher.

Prof. Gabriel S. Timar of the University of Toronto, Canada, says that exposure to high levels of noise or music can have harmful physical or emotional effects. In a recent report he states that impacts of noise may be manifested in serious psychological disturbance or severe – sometimes extreme – pain in the ear.

“The physical damage to the ear could be temporary hearing loss, manifested in reduced perception of low-level sound. If the patient is removed from the noisy environment, recovery could be expected within a couple of months.”

Permanent loss of hearing is possible, he states. It means that the patient will not perceive low-level sounds, and the condition may be corrected only with the use of electronic hearing aids. Although some individuals may be more sensitive to noise than others, the exposure to loud (100 decibels) music – so fashionable today – may eventually lead to a 10- to 15-decibel hearing loss at the lower end of the perception range.

“The extent of the loss in one’s hearing depends on the level and duration of the exposure. It is likely that one hour of exposure to 100-decibel noise may cause short-term hearing loss, with a recovery period of one to five days.

Continuous exposure to high levels of sound, in the vicinity of 90 decibels, for a period of more than five years may eventually lead to 15 to 20 decibels of hearing loss,” the report continues.

Professor Timar goes on: “Apart from the direct physical effects to one’s hearing, the indirect physiological effects of continuous exposure to noise pollution can be significant. Heart disease, raised blood pressure, change in the pulse rate can be related to extended exposure to noise.”

Severe emotional impact

The emotional impact, he says, could be far more severe. Continuous exposure to elevated noise levels will cause irritability, anxiety, stress and, in extreme cases, depression.

In noisy factories, unless the workers are protected with earplugs or specially designed muffs, mental fatigue and loss of concentration is common, leading to lower levels of productivity and accidents.

At construction sites where hydraulic equipment (jackhammers) is used, accident rates have been significantly reduced by the introduction of earmuffs for the operators of the machinery.

In a community the impact of high noise level is significant, he says, since it interferes with sleep as well as conversation.

The psychological effects are far-reaching – perhaps even to the point of contributing to social problems like domestic abuse. Professor Timar recommends that public health officials look into the physical and emotional impact of noise pollution, especially in communities exposed to constant high-decibel noise, such those near busy airports.

Of even more concern is the impact of noise on children. A chapter on noise pollution in the book Silent Scourge: Children, Pollution, and Why Scientists Disagree (Oxford University Press, 2003) states:

“Everyone knows that noise that is loud enough can damage a person’s hearing. … this chapter concentrates mainly on what researchers call the ‘nonauditory’ effects of noise, or how noise affects well-being aside from its effects on our hearing organs. The nonauditory effects of noise in children fall into two main categories: reading and other aspects of cognitive performance, and stress-related responses such as annoyance, blood pressure, secretion of stress-related hormones, and mental health.

“These two categories are also linked to the auditory effects of noise. A very important auditory effect of noise is interference with the intelligibility of speech. Hearing other people talk is critical to children’s early language development. But trying to hear someone talk in a noisy environment can produce other nonauditory effects. Memory and performance can be impaired because of the extra effort required to decipher speech. Mood can also become more negative, and the person feels tired or stressed… auditory and nonauditory effects of noise are often interlaced.”

Reducing noise around us

According to a World Health Organisation (WHO) report to the United Nations Conference on Environment, “Of all environmental problems, noise is the easiest to control.”

But the possibility of control arises only after we become aware that we need to control the unbearable sounds that surround us. Here are a few ways it could be tackled.

1. Reduce noise at the source. Development of silencing devices for use in aircraft engines, trucks, cars, motorcycles, industrial machines and home appliances would be an effective measure. Workers can be protected with devices such as earplugs and earmuffs. Changes in design and operation of machines, vibration control mechanisms, soundproofing and sound-absorbing materials will reduce noise volume.
2. Control traffic noise. Traffic racket can be reduced by imposing noise limits on vehicular traffic, banning the use of horns in certain areas, and properly planning main traffic arteries, industrial parks, amusement areas and residential estates. The creation of silent zones near schools and hospitals and the redesigning of buildings to make them noise-proof is another approach. Other measures might involve reducing traffic density in residential areas and introducing affordable, reliable public transit.
3. Control indoor noise. Where outdoor noise levels are high, there are ways to reduce the impact on nearby buildings, some of which have to do with building design, location and landscaping.
1. Locate in the building as far as possible from the noise source. The noise level drops about 6 decibels each time the distance from the source is doubled.
2. Plant trees and shrubs in front of buildings to absorb sound.
3. Locate non-critical areas such as corridors, kitchens, bathrooms, elevators and service spaces on the noisy side and critical areas such as bedrooms and living spaces on the quiet side.
4. Back-to-back bathrooms should be avoided unless they are effectively sound-insulated. Bathrooms, kitchens and laundry rooms should not be adjacent.
5. Bathroom walls, floor and ceiling should be sound-insulated, and windows should be double- or triple-glazed.
6. Noisy toilets can be replaced with quiet, siphon jet–type flush systems.
4. Road noise. Vegetation buffers should be created in the urban areas on the island. There should be more roadside plantations.
5. At present, there is no specific and detailed legislation to control noise pollution. The government needs to pass such legislation. It should include severe restrictions on hot-rod exhausts (and inefficient muffler systems) and vehicle sound systems that broadcast to the neighbourhood, and restrictions on where and when fireworks may be set off. There are many more … you know what they are!

These are some solutions to the environmental problems caused by noise pollution. But – just as with every other problem our society throws out – do we want to change so we can reduce noise?

Perhaps if we spent more time thinking about how we affect our neighbours – especially the elderly – when we rev up that hot car at 2 a.m., we might just quieten our lives, and thereby improve them.

Remember, “Do unto others as you would have them do unto you!”

ECO-COMMENTARY
by the Green Hornet

2 comments:

  1. Thanks for taking the time to discuss this, I feel strongly about it and love learning more on this topic. If possible, as you gain expertise, would you mind updating your blog with more information? It is extremely helpful for me.
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  2. There is so much NOISE around us that we find silence worrying! That is a big problem in the UK these days (and everywhere TBH)

    I love the sound of the sea and sitting on the beach just listening and thinking - something we all do too little of.

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