Acoustic barrier panels are used in a variety of configurations to be placed either between the noise source and the receiver to block the path of sound (acoustic barrier walls) or to isolate the noise source completely (noise control enclosures).
Acoustical performance of barriers is measured according to two different characteristics:
1. The ability to BLOCK SOUND is expressed as the STC (Sound Transmission Class) rating.
2. The ability to ABSORB SOUND is expressed as the NRC (Noise Reduction Coefficient) rating.
The most common concern when searching for panels is the density or mass of the panel, which is correlated to it's ability to block sound transmission through the panel - i.e. the greater the mass, the better the ability to block sound. The thickness of the panel is another factor, since thicker metal and vinyl panels typically have a deeper cavity to accommodate more acoustical media; which theoretically increases sound absorption. The type of materials used for sound blocking and absorption can have dramatically different effects on performance. Thus, the type of panel, whether concrete, vinyl or metal is an essential decision to be made when determining which panels are best suited for the application.
Wood panels should NOT be considered for either noise (unwanted sound) blocking or absorption as they are ineffective at both.
Concrete panels are relatively low cost and extremely durable. Offered as a one-size fits all solution, they typically are not customizable. They offer high density or mass and excellent sound transmission values, which means they are somewhat effective at blocking sound from going through the panel. This also means that they simply reflect or "bounce" sound back and do not offer good sound absorption. In some cases, this causes a buildup of sound on the source-side of the barrier. We have all experienced this when driving through a tunnel, or under an overpass, with a loud vehicle beside us: the reflected noise is amplified at a very high level due to the sound being reflected back off of the concrete surfaces.
The purpose of using vinyl acoustic panels is for good noise absorption while adding aesthetics. They are primarily used for indoor applications and are available in several colors, profiles and abuse resistant textures. Vinyl panels do not have the density or mass of metal or concrete panels, therefore they are not very effective at blocking sound transmission through the panel. Durability is also important to consider when it comes to vinyl panels especially in outdoor applications, since exposure to extremes of heat, cold, sun, wind, freeze and thaw can have detrimental effects on the longevity of vinyl products in the environment. Surface burning/smoke development characteristics need to be considered for indoor use.
Modular noise control metal panels typically have a much higher mass and density which leads not only superior longevity, but also outstanding noise reduction. They are ideal for outdoor applications due to excellent structural rigidity and construction material. They are constructed to withstand the extremes of outdoor conditions and to can handle extreme heat, UV, exhaust and gases. They will not become brittle with time or low temperatures and will never crack thanks to their factory base coat which ensures a lifetime of durability. Engineering modular acoustic panels are offered in optimized and customizable widths and lengths allowing for pleasing aesthetics. Additionally, metal acoustic panels are 100% recyclable, environmentally friendly and non-combustible.
dBNR's Nois-eNvelope™ offers architectural environmental acoustic barrier walls, panels and enclosures which provide superior noise reduction with industry-leading results for both the Noise Reduction Coefficient (NRC) and Sound Transmission Class (STC) ratings.For product details regarding materials, panel thicknesses, construction, paint finishes and test data please visit www.noisenvelope.com.
The choice between concrete, vinyl and metal acoustic panels is based on application and the environmental factors in which the panels will be in.
Concrete should only be used outdoors and for moderate noise blocking; Vinyl panels are suitable for indoor spaces as they are able to meet absorptive acoustical requirements while achieving exceptional aesthetics. Metal panels have superior absorptive and noise blocking characteristics and are ideal for indoor and outdoor, environmental and industrial applications as they are able to withstand extreme environments.
Therefore, the application, the durability, the construction requirements, and the environmental factors should all be taken into consideration when selecting the type of panel you need. dB Noise Reduction's Nois-eNvelope™ metal panels have extremely high performance ratings and offer excellent value whenever noise reduction is required.