Noise hazards
Noise is a common phenomenon (at work, at the place of residence and rest), which causes many negative effects on human health. Health problems, that can arise as a result of noise are m.in. difficulties in communication and concentration, stress and irritation, sleep and circulation problems, as well as a negative impact on the psyche and performance Therefore, it is important ,that the apartments are designed and constructed in a way that allows residents to rest and work freely.

Sound level
Sound level is measured in decibels (Db) Decibel is the ratio of the measured sound pressure to the threshold of audibility.
Sounds of equal intensity, but of different frequencies are not equally perceived by the human ear. Changing the volume twice for low and high frequencies corresponds to changing the sound level by 6 Db, whereas for the average frequencies such an impression is caused by a change of 10 Db.
The perceived change in volume by a person depends on his output level, and so e.g.. for sound with level 0 dB will already be felt an increase of 2 Db, while for sound with level 90 dB change by 2 dB will not be felt.

Transmitting and absorbing sound
Sound from neighboring rooms is transmitted not only through the walls, but also through the connections of the walls with the ceiling and through the ceiling. To avoid excessive noise, properly insulate the walls, connections of walls with the ceiling and the ceiling itself.
When a sound wave hits a partition in a given room, some of this energy is reflected back into the room and the remainder enters the partition.. In the partition itself, part of the sound wave is absorbed and the rest is passed through the material to the adjacent room. How a given material absorbs sound is expressed by means of a sound absorption coefficient a (alpha). This coefficient is presented as a frequency and ranges from 0.00, which means the total reflection of the sound to 1.00, which means total sound absorption.
Glass wool should be used for sound insulation because the energy of the sound wave is absorobated by glass wool fibers – through vibrations, glass fibers convert sound wave into thermal energy.