What is noise?
Noise refers to all loud sounds that people do not want to hear. This sound is produced by vibrations that spread evenly through the air in the form of sound waves. The louder the sound, the more it will appear to be an unpleasant noise. Not only too high volume, but also certain frequencies can be unpleasant. Long-lasting or high-intensity noise disturbances can negatively affect people's work efficiency and even cause illness.
For example, offices, especially open office areas, are often flooded with loud background noise, which will greatly affect people's health, comfort and work efficiency. The stone floors, floor-to-ceiling glass and other highly reflective surfaces and spacious spaces used in modern buildings are even more disadvantageous for this situation. Sound waves are reflected off these hard surfaces, forming long-lasting echoes that are often uncomfortable and tiresome. Therefore, it is very important to use anti-noise devices to eliminate noise interference for health.
How do noise suppression devices work?
There are different measures to prevent noise.
One way is to "enclose or isolate" the noise. Loud machines, for example, can be isolated from the surrounding environment by means of a special housing device that acts like a soundproof chamber, which reduces the sound emitted by the production process.
In addition, the noise level can also be reduced by means of noise reduction and sound insulation.
One of the oldest soundproofing materials is kapok lightweight fiberboard made from renewable raw materials. A normative standard for this material was established as early as 1938 and was superseded by the European standard EN 13168 in 2007.
In addition, perforated acoustic components made of metal, wood or plasterboard, such as sound-absorbing perforated boards, are often used in construction engineering.
In order to improve indoor acoustics, this type of sound-absorbing sheet is equipped with sound-absorbing non-woven or mineral fiber mats on the back.
The application of non-woven fabrics in the field of anti-noise goes far beyond that. Its properties allow it to be used in a variety of different sound and sound insulation devices.
Anti-noise with non-woven fabric
Non-woven fabrics have different properties, so they can achieve different acoustic effects. Different surface properties can act to diffuse or "absorb" sound waves. The porous structure of the non-woven fabric enables the vibrating air molecules to enter the non-woven fabric structure. Here the air molecules rub against each other and with the fibers of the non-woven fabric, thereby converting the kinetic energy of the molecules into heat lost by friction. This reduces the sound field and reduces the noise level.
Nonwovens are increasingly being used for sound insulation and noise reduction. In the automotive industry, for example, nonwovens are used to reduce the transmission of ambient noise such as engine noise and traffic noise into the interior of the cabin. The sound-absorbing properties of non-woven fabrics are also utilized. For example, fix the muffler behind the carpet or dashboard to reduce the sound field inside the cabin.
In interior acoustic design, non-woven fabrics are increasingly used as sound-absorbing "design elements". Examples include single panels mounted on walls and/or ceilings, full-face wall coverings and suspended ceilings, sound-absorbing partitions for open office areas, or entire pieces of furniture made of felt.
When it is used for noise reduction and sound insulation, a specific type of noise reduction device is mainly used as far as possible, for example, it is made by mixing natural fibers such as recycled fibers or wool fibers with synthetic fibers.
The sound-absorbing non-woven fabric can not only improve the indoor acoustics, but at the same time can be beautifully integrated into the overall design of the room.