Noise and vibrations
Sounds or noise?
Finnish legislation defines noise as sounds that are detrimental to the health, or which otherwise spoil people’s enjoyment of the environment or hinder their work. As a rule-of-thumb, noise is also often simply defined as undesirable sounds.
The legal definition thus stresses the significant socio-economic impacts of noise – including such factors as health care costs, the reduced efficiency of work and decreased property values. The shorter definition contrastingly emphasises the subjective nature of noise problems. Indeed the same sound may represent a serious nuisance to some people, while giving other people considerable pleasure.
Traffic, industrial processes, construction, maintenance work on properties, and outdoor events may all result in noise pollution – a phenomenon similar in many respects to other forms of pollution.
Noise is emitted through the air in the form of sound waves, but the same sources may also generate harmful vibrations transmitted through the ground and other solids, particularly where heavy traffic, heavy industrial processes, construction, quarrying and other activities using explosives are concerned.
Different sources of noise are typically compared according to the number of people living in the area affected by noise over a certain level. During the daytime, noises louder than 55 decibels are considered to constitute a disturbance. Noise levels over 65 dB have noticeable physical impacts on people, and continuous noise over 85 dB may damage people’s hearing more permanently.
Noise limit guidelines have been set for different types of environment at different times. For instance, noise levels should not exceed an average of 55 dB in people’s gardens or on the balconies of their homes during a single day. In reality, many people in Finland live in areas where this limit is surpassed; but new homes and residential areas 0should in future be carefully planned to avoid such problems.