The acoustic picture of the world is an integral part of our world perception. It is one of the bases for our ability to get oriented in the environment. But in the modern world people are more and more exposed to undesirable – too loud and irritating – sounds. As the threshold of sound sensitivity differs from one person to another, it is impossible to state what frequency and volume of sound should be considered as noise. Usually we call noise any sound that causes discomfort. Lasting exposure to loud noise has negative influence on hearing and may lead to irreversible changes in the system of auditory analyzer.
Unacceptable noise level has become a habitual part of living in a modern city. We practically never hear complete silence. Even if it seems to us that we don’t hear a sound we are still accompanied by the background noise produced by working household appliances, traffic, the underground and so on. From the environmentally friendly point of view, noise is considered as a type of pollution. Even the everlasting presence of background noise in itself has a negative effect on our auditory analyzer. As well as any other organ, in the conditions of continuous functioning our hearing organ “wears” and the sharpness of auditory perception decreases. The higher the noise level around us, the faster hearing loss will progress.
High level noise is even more dangerous. What noise should we consider as excessive and therefore hazardous? No doubt, we may call hazardous any noise that causes discomfort with the listener – and even more so if it causes physical pain in the ears. In order to prevent damage to the auditory analyzer you should try and make your acoustic environment maximally healthy. If it is possible, try to avoid any noise that causes a sensation of discomfort or pain. If you have to work in the conditions of excessive noise, it is necessary to use hearing protection – special ear plugs blocking hazardous noise. The highest noise level permissible at the working place is in most countries set by legislation to the limit of 85 dB. It is considered to be the maximum permissible noise level exposure to which for eight hours doesn’t do harm to the ear.
Of course, the maximum level of noise that may be called permissible varies – people perceive the volume of sound in different ways. But generally speaking, to preserve the health of your ears you should avoid places with a hazardous noise level. First of all these are places where you can hear obviously undesirable and irritating noises – industrial zones, building sites, places where heavy machinery is at work. But you also should know that some sounds which may seem pleasant to many people can also be considered as a hazardous noise. We are speaking about the extremely loud music that you can hear at concerts and in nightclubs. Sound volume in places like these often by far exceeds the permissible level. To block undesirable noise in such cases it is recommended to use protective earplugs.
Besides, an extremely strong negative influence on our auditory organ is produced by listening to loud music through earphones which is so popular nowadays. Using such seemingly harmless device as an M3 player may seriously jeopardize your hearing. Listening to music at the maximum volume and for a long time is especially harmful.
For people with a hearing loss staying in noisy environment is connected with particular difficulties. A hearing impaired person always has to strain in order to understand his interlocutor’s words and to identify the direction of sound. Noisy conditions make this problem even worse – the already hampered process of sound flow perception is complicated by the need to differentiate important sounds from undesirable ones. That is why in choosing a hearing aid one must pay special attention to whether this or that model has the function of noise reduction. As to the latest generation hearing aids, almost all of them feature modern sound-filtering systems. Due to their “smartness”, they filter off undesirable noises and amplify the sounds that are especially important for normal life – for example, human speech. That is a considerable advantage over the previous models of hearing aids capable only of amplifying all sounds to the same degree