Why isolate acoustically
In terms of quality of life, a major concern for millions of people in Italy is the excess rumore.Gli effects on the health and life report confirms that the problem Noise must be considered seriously. The house, for example, is the place where people aspire to enjoy more relaxation and detachment from the pressures of the outside world, but the presence of noise, even a very low level, produced by the neighborhood, a condition sometimes can be so irritating to generate a level of nervous stress which implies negative consequences for health such as insomnia, hypertension or migraine. Hence the need for good sound insulation
In terms of quality of life, a major concern for millions of people in Italy is the excess rumore.Gli effects on the health and life report confirms that the problem Noise must be considered seriously. The house, for example, is the place where people aspire to enjoy more relaxation and detachment from the pressures of the outside world, but the presence of noise, even a very low level, produced by the neighborhood, a condition sometimes can be so irritating to generate a level of nervous stress which implies negative consequences for health such as insomnia, hypertension or migraine. Hence the need for good sound insulation
intrusive noise: a growing problem
The level of conflict due to noise problems in Italy saw a significant increase in recent years. In the period between 1986 and 1996 there was a marked increase of such phenomena. According to recent research market, it has been pointed out that about three quarters of all households suffer from problems related to noise from traffic, business, technical equipment, etc.. or simply from neighbors. Almost half of these complaints about aircraft noise and intrusive to traffic coming from neighboring apartments.
There are many reasons for this increase in noise intrusive. The number of noisy appliances has increased dramatically since the '50s, when the rules defined for the first time a set of standards for noise control. Currently there are many more households owning appliances such as washing machines, telephones, vacuum cleaners and systems entertainment such as television, stereo and computer.
The improvement of living conditions and the small average size of housing units has resulted in an increased sensitivity to noise intrusive highlighting the need to live undisturbed in a personal space, and reduce interference from outside.
The regulations tend both to determine the maximum allowable noise in urban areas that reduce the exchange sound between apartments. There is therefore hope that in the near future we can achieve more acceptable levels of noise and comfort noise
internal control intrusive noise
The building regulations require specific design features to ensure proper sound insulation, according to two different categories: *
air noise - generated within the built spaces, such as headings, stereos or televisions;
* Noise caused by traffic - generated by the steps or the fall of objects on the floor.
Traditional solutions to the problems of aircraft noise are the construction of massive structures or the use of layers and insulation materials of great thickness, while the sound transmission through floors from foot traffic is still faced with the inclusion of Resilient layers. In many cases these solutions are impractical, especially in renovation or routine maintenance.
The level of conflict due to noise problems in Italy saw a significant increase in recent years. In the period between 1986 and 1996 there was a marked increase of such phenomena. According to recent research market, it has been pointed out that about three quarters of all households suffer from problems related to noise from traffic, business, technical equipment, etc.. or simply from neighbors. Almost half of these complaints about aircraft noise and intrusive to traffic coming from neighboring apartments.
There are many reasons for this increase in noise intrusive. The number of noisy appliances has increased dramatically since the '50s, when the rules defined for the first time a set of standards for noise control. Currently there are many more households owning appliances such as washing machines, telephones, vacuum cleaners and systems entertainment such as television, stereo and computer.
The improvement of living conditions and the small average size of housing units has resulted in an increased sensitivity to noise intrusive highlighting the need to live undisturbed in a personal space, and reduce interference from outside.
The regulations tend both to determine the maximum allowable noise in urban areas that reduce the exchange sound between apartments. There is therefore hope that in the near future we can achieve more acceptable levels of noise and comfort noise
internal control intrusive noise
The building regulations require specific design features to ensure proper sound insulation, according to two different categories: *
air noise - generated within the built spaces, such as headings, stereos or televisions;
* Noise caused by traffic - generated by the steps or the fall of objects on the floor.
Traditional solutions to the problems of aircraft noise are the construction of massive structures or the use of layers and insulation materials of great thickness, while the sound transmission through floors from foot traffic is still faced with the inclusion of Resilient layers. In many cases these solutions are impractical, especially in renovation or routine maintenance.
Sound Sound is a form of energy produced when a source generates waves (rapid variations in pressure) in half. It is perceived when the waves reach the receiver. The frequency of sound, measured in Hertz (Hz) is defined as the number of waves generated per second.
The intensity of a sound depends on the pressure variation inside the medium. The key measure of the intensity is the sound pressure level in decibels (dB). The sound pressure level in decibels of sound pressure represents an increase compared to a conventional reference pressure equal to the threshold of audibility of a sound to the human ear. E 'on a logarithmic scale, in practice this means that, in the presence of a point sound source, doubling the effective sound pressure level sound pressure increases by 6 dB.
The human perception of the sound intensity depends on the peak, or the frequency of the sound: the ear is less responsive to sounds characterized by very high peaks and very low compared to those in the intermediate range (500 - 4000 Hz). The experts suggest that when a sound pressure level is reduced by 10 dB the human ear perceives the noise as half. The
the sound recording as a single value may be sufficient for most everyday uses, but is not accurate for uses sound as the single value may mask substantial changes in noise levels at various frequencies. Therefore, the sound levels are measured on different frequencies, usually over a range of 6 octaves (125, 250, 500, 1000, 2000, 4000 Hz) bands of a width of 1 / 3 octave. The sound transmission
The sound is transmitted between different parts of the buildings and between adjacent buildings in two ways.
»Sound aereoQuando the sound generated inside a room reaches the areas that surround it, a part of its energy is reflected, some is absorbed in the element structure that surrounds the environment and finally to another party generates vibrations 'inside the element itself. These vibrations in the presence of sufficient energy, they produce noise on the other side of the element itself and spread into the neighboring country.
"Noise from calpestioL'impatto directly on the building structure, such as steps, a hammer, a falling object or a closed door with force, causing the vibration of the structure and produces sound waves on both sides of the affected area.
Noise control measures necessary to reduce noise transmission within buildings and between buildings and the other will vary depending on the type of structure and its reaction to sound energy. The main factors influencing the behavior of structures, characterized by the noise include:
"The mass is a need for greater amounts of energy to transmit vibrations in a solid structure and density in a light, a massive structure is therefore less prone to the transmission of sound;
'rigidity: when a component is made up of different parts of the level of sound transmitted depends on the stiffness of the connections between these parts, such as a wall or a link layer in a resilient floating floor. The stiffer is the connection the greater the sound transmission between different parts of the structure;
'absorption: the components that absorb the sound energy by converting it to reduce heat transmission noise through the structure of the building.
'cavities: cavities favors the reduction of sound transmission by isolating different parts of the building elements, the width of the cavity and the number of connections that go through influence on the extent of reduction.
Side drive transmission side or flanking occurs when the sound wave is transmitted from one space to another contiguous or indirectly through adjacent parts of the structure.
This can occur, for example, when an impact sound is transmitted from one environment to another underlying not only directly but also through the floor by the side wall of the carrier. Other cases are common side transmission such as ceilings and partition walls, or pipes and ducts. To be truly effective solutions for noise reduction should take into account these possible transmissions.
unit to reduce noise Noise level
* Rw (evaluation index of the sound) - Laboratory measurement of noise reduction capability of a piece of property. *
R'w (evaluation index of the apparent sound reduction index) - Measurement of airborne noise between the two environments. Takes into account not only the direct transmission through the partition in question, whether the transmission occurs through lateral structures of the environment and the receiving source. Higher values \u200b\u200bdenote better performance.
* DnT, w - Measurement of the reduction in sound levels between an environment and the other, higher values \u200b\u200bdenote better performance.
sound insulation
* Ln, w - Laboratory measurement of the transmission of impact sound
* L'n, w (index to assess the level of sound insulation standard) - Field measurements of impact sound transmission between rooms , lower values \u200b\u200bdenote better performance.
* L'nT, w - Measure the level of noise impact transmitted between environments, lower values \u200b\u200bdenote better performance.
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