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What is noise? Any unpleasant sound is noise. It's something we don't like. It's something that makes us cover our ears. The wail of a fire engine, a clap of thunder, the screech of a car's tires when the brakes are put on suddenly. How much sound is too much? At what level does sound become noise? Well, today sound can be measured scientifically. The level of sound is measured in decibels.
A decibel meter is used to register sound. Zero decibels are equal to the faintest sound heard by the human ear. A decibel meter in a quiet bedroom may register around 35 decibels. In a classroom during a quiet period, it may register around 50 decibels. This level is comfortable on the ears. It is said that most people speak in a range between 45 and 75 decibels. Noise damages ears at 85 decibels. Hearing loss can begin when the noise level goes above 100 decibels, and actual pain is felt at 140 decibels. Some people, however, may experience pain at a lower level.
Noise pollutes our environment just as much as smoke, foul water, dirty air, and litter. It can cause illness and deafness. The human body never gets used to the noise. It continues to react even though a person thinks he or she has become used to all the surrounding noises. For instance, Naseer who lived in an apartment on a busy street often boasted that he could sleep through any kind of noise. He claimed he just didn't hear it. Well, Naseer could sleep through the roar of traffic and the blare of a television set in the next apartment, but he didn't know that while he slept his body was reacting to the stress of the noise.
A doctor in West Germany, after studying the effects of noise, concluded that sounds heard by persons when they are asleep can cause danger to their hearts and blood vessels. Maybe this was the reason why Naseer had headaches. Noise causes the blood vessels in the brain to expand. It brings on the pain. Another doctor was researching the effects of loud music by talking to players in a rock band.
One of them called out, "Speak up, Doctor, we can't hear you". The doctor discovered that all the players suffered from some hearing loss and two of them were partially deaf. The noise level of the music they played ranged from 105 to 115 decibels and they played for more than eleven hours every week. It's the length of time and often hours and hours of being exposed to loud noises that damage the sensitive part of the inner ear. What can you do? If you start thinking about the harmful effects of noise, you will become quieter yourself.
There are many steps you can take to cut down noise. At school, for instance, instead of slamming books on a desk, place them quietly. Instead of walking noisily through the halls, walk quietly. At home use one mechanical device at a time.
In other words, don't run the vacuum cleaner and the washing machine at the same time. Turn down stereos, radios, tape recorders, and televisions sets. And don't turn on more than one at the same time. Many cities have passed strong anti-noise regulations. Progress is being made towards a quieter world, but if we want to get rid of the rattle, bang, and roar all around us, we have to start being quiet ourselves.