Välismüra

Välismüra refers to unwanted sound that originates from outside a building and penetrates the interior. It is a significant factor in indoor environmental quality and can affect comfort, concentration, and well-being. Common sources of välismüra include traffic noise from roads, aircraft noise from nearby airports, industrial noise from factories, and general urban sounds like construction or public events.

The perception and impact of välismüra depend on several factors, including the intensity and frequency of the sound, the duration of exposure, and individual sensitivity. High levels of välismüra can lead to annoyance, stress, sleep disturbance, and reduced cognitive performance. In residential settings, it can significantly decrease the quality of life.

Mitigating välismüra typically involves a combination of strategies. At the source, efforts can be made to reduce noise generation, such as implementing quieter machinery or traffic calming measures. More commonly, attention is focused on the building envelope to block sound transmission. This involves using sound-insulating materials in walls, windows, and doors, as well as ensuring proper sealing to prevent sound leaks. Building orientation and site planning can also play a role in minimizing exposure. Urban planning and zoning regulations are also employed to separate noise-sensitive areas from major noise sources. The effectiveness of these measures is often assessed using acoustic measurements and by considering factors like sound transmission class (STC) ratings of building components.