Paragraph 1

The old adage extols the virtue of silence by claiming it is golden, yet experience tells us that silence is as hard to come by as the precious metal itself. The benefit of silence to the human ear is scientifically demonstrable. Less superfluous noise; less impairment to the hearing. Yet this precious commodity is no longer valued. Noise is ever present in modern life and is an accumulative experience. The ill effects of noise pollution are of two kinds: acute – exposure to an individual instance of a very loud noise, such as a gunshot or explosion; and chronic - the experience of too much noise over an extended period of time.

Paragraph 2

City and urban dwellers exist in an increasingly noise-ridden environment, and it is now almost impossible to escape exposure to high noise levels. Even if we exclude the more obvious sources of noise pollution such as jet plane engines, road works, power tools, loud music at dance parties and so on, it is clear that noise is a constant and often unwelcome companion. We have only to walk through a suburban shopping mall or department store, or catch a bus or train to be subjected to noise levels that a few decades ago would have been considered beyond human endurance. The popular practice of "layering" sound, by adding a louder source of noise to that which already exists in order to mask it, merely compounds the problem. Because of the accumulative nature of noise abuse, constant noise is worse than noisy periods interspersed with silence.

Paragraph 3

Our noise level acceptance threshold is rising in step with the number of persons developing hearing problems. Data available from a recent survey conducted by the Australian Bureau of Statistics show that 7.4% of people over 14 years of age have some discernible hearing problem. According to the survey, 24.6% of the 7.4% of persons with affected hearing have problems caused by subjection to a constant barrage of noise, either at work, in the everyday living environment, or as the result of a particular choice of leisure activity. The problem is most severe for males aged between 25 and 64 years of age, 9.1% of whom have a hearing disability, and for which the cause is constant noise in 44.4% of cases.

Paragraph 4

Of current concern to acoustical engineers and psychologists at the National Acoustics Laboratories in Sydney, Australia, is the potential for damage to the eardrum caused by the transmission of loud sound through earphones placed directly into the ear canal. An almost universal fad among young people, the pocket-sized radio-cassette player (commonly known by the brand name "Walkman") may be exposing its owner to greater than the maximum safe dosage of noise recommended for industrial workers – 90 decibels^* over a period of 8 hours. This dosage, called Dose 1, can be achieved much sooner by exposing the ear to only slightly more than 90 decibels. Increases to the decibel level logarithmically shorten the exposure time required to reach a given dose. For instance, to achieve Dose 1 in 4 hours, it is necessary to raise the decibel exposure level by a mere 3 decibels.

Paragraph 5

One danger posed to young ears is that the peak sound level from these radio-cassette players is often far too great; at high volume it is all too easy to receive Dose 1 in a short period of time. Any further noise heard above 90 decibels that day and the recipient is causing measurable damage to his or her ears. Another danger is the likelihood of a change in the pain threshold of noise resulting in users compensating by increasing the volume to levels way above what is considered safe. Finally, insertable earphones block the ear canal, thereby further increasing the noise level absorbed.

Paragraph 6

But perhaps the most alarming potential for danger caused by insertable earphones is the ease with which the listener can exceed the safe time length of exposure to noise. The small earphones can be comfortably worn for extended periods of time. What is more, there is the danger of falling asleep with the earphones inserted, leading to an accumulation of excess noise while unconscious.

Paragraph 7

Noise abuse soon leads to varying degrees of hearing loss. What may begin as an acute temporary condition, in time becomes a chronic and irreversible disability. A common complaint is "tinnitus", or a "ringing in the ears" which fails to subside after the ears are subjected to a short but extreme dose of noise. It is an exhausting condition that can seriously threaten the composure of the sufferer who can be driven to near madness. It is believed the composer Beethoven was particularly aggravated by this malady. At present, there is little that can be done in the majority of cases, although the victim might be able to obtain some temporary relief by using a masking device which blocks out the offending frequencies of sound with other, less annoying frequencies.

Paragraph 8

Inevitably, though, years of excessive noise accumulation take their toll and partial or complete deafness results. If silence is the cure for ailing ears (or, at least, the best way to prevent further deterioration of one's hearing), it is sobering to realise that it is also the unfortunate and permanent curse of a lifetime of noise abuse caused by ignoring the warnings.

^* decibel:  standard unit of sound measurement

Questions 1 – 7

Match the headings below with paragraphs 1 – 8 in the reading passage entitled "Hearing Problems".

There are more headings than required.

The last paragraph heading has been completed for you as an example.