Category Archive: Uncategorized

What Is STC Rating? (Sound Transmission Class Rating)

Industrial noise control is essential for enclosure design, operator cabins, and recreational vehicles.. When noise levels get too high, it can be disruptive, frustrating, and dangerous. Manufacturers and installers facing major issues may need to further soundproof structures.

STC ratings, or Sound Transmission Class ratings, create a relatively standardizing rating system that measures sound transmission (as opposed to sound attenuation or decibels). STC ratings help designers confirm the degree of soundproofing they can provide in a given space.

Learn more about how STC works, what ratings to aim for, and how to decrease unwanted sound transmission across your structures.

What Is STC?

Sound Transmission Class (STC) is a single rating number system that evaluates how effective different materials are at blocking sound. When more sound is being blocked, the material scores higher. It’s a generalized scale, meaning that loud sounds may be faintly audible (high scores) or normal conversational volumes are audible (low scores).

Most enclosures will have different materials for their floors, ceilings, walls, and doors, as the materials within each area uniquely contribute to overall soundproofing.

While STC measures vocal noise and relatively high-frequency noises, it is less accurate when measuring low-frequency noises such as machinery or music.

What Is a Good STC Rating?

As a general rule, the higher the STC rating is, the better. Walls, floors, and ceilings may each warrant different levels of soundproofing. An operator cabin may require more soundproofing for walls, headliner, and floors while a generator would require a more basic treatment.

If you want to construct environments with very little external sound interference, you will need to achieve a higher STC rating with your soundproofing. For instance, an apartment should generally rate on the higher end of the scale so residents can perform daily functions with adequate privacy.

How Is STC Measured?

While STC ratings provide a generalized, rough understanding of how soundproof a structural surface is, they don’t directly measure decibel reduction. The STC ratings follow specific laboratory testing procedures that adhere to ASTM standards.

Laboratories can determine the STC rating of materials (or combinations of materials) by measuring transmission loss and plotting it against the frequency of the sounds.

What Is a Good STC Rating for Windows?

Windows are harder to soundproof than other surfaces like floors and walls because it’s much harder to layer effective materials.

Single-pane windows typically have a rating of 26-28, and it’s hard to significantly raise it. However, builders can install double-pane windows and add more insulation around the windows to mitigate sound overall.

STC Rating Chart

Use this STC rating chart as a rough guide to the different STC ratings for soundproofing materials:

• 25: There is no functional soundproofing, and quiet conversations can easily be overheard
• 30: Quiet speech is muffled, but conversations at normal volumes are audible
• 35: Loud speech is clearly audible
• 40: You can hear loud conversations next door but not clearly understand them.
• 45: Conversations can be private
• 50: Loud conversations and sounds are muffled but faintly audible
• 60+: Soundproofing is very good, and even loud conversations will be hard to overhear

STC Rating vs. Decibels

STC ratings measure how much sound is being blocked, while decibels (dB) measure the volume of the sound. The two concepts are related but not identical; acoustic absorbers can both have a high STC rating and reduce decibels.

Consider these common sound thresholds:

• 10 dB: Sound is now audible
• 35 dB: Whisper volume
• 55 dB: The volume of a large transformer at 200 feet
• 70 dB: Normal speech from one foot away
• 85 dB: Pneumatic drill 50 feet away
• 95 dB: Subway train 20 feet away
• 105 dB: Operator’s experience of a pneumatic hammer’s volume
• 120 dB: Jet taking off from 200 feet away

Learn More About STC Ratings From Technicon Acoustics

Technicon Acoustics specializes in industrial noise control and vibration-damping solutions. We provide solutions for construction equipment, marine applications, power generation equipment, and trucks.

Contact us today to learn more about our products and their applications or to request a quote.

Open Cell Foam vs. Closed Cell Foam

The material you select for sound insulation projects will significantly impact the level of sound absorption and attenuation you can expect to achieve. Open cell and closed cell foams are two effective material options for such applications, each with its own unique structure, benefits, and uses. Read on to discover how open cell and closed cell foams are both alike and distinct from each other to help decide which option is the right choice to address your acoustic needs.

Open Cell Foam vs. Closed Cell Foam Structure and Composition

Recognizable for its porous structure, open cell foam is constructed from an interconnected cell network that facilitates airflow for heightened breathability and air permeability. Its open cells also make the material more flexible. In contrast, the cells found in closed cell foam are sealed off, meaning that air and water can’t pass through them. Closed cell foam has a higher density, making the foam material quite rigid while offering enhanced capabilities for sound absorption and attenuation.

Performance of Open Cell Foam vs. Closed Cell Foam

While each foam type is advantageous in its own way, the following is an overview of open cell and closed cell foam performance:

• Durability. Closed cell foam holds up better than open cell varieties, giving it good application versatility and the durability to handle insulation projects.
• Moisture resistance. Closed cell foam offers better resistance to moisture thanks to its impermeable structure. Open cell foam has a higher chance of developing mold because it runs the risk of absorbing and holding moisture.
• Thermal insulation. Open cell foam’s breathable, porous structure lends it to applications within controlled indoor environments. Conversely, closed cell foam is an optimal choice for outdoor applications and settings that will expose it to moisture due to its higher R-value.
• Sound absorption. Open cell foam exhibits superior sound absorption capabilities due to facilitating airflow within its cell network. Besides having a lower density, this material is softer and thicker, minimizing sound waves with greater efficiency than closed cell foam.

Closed Cell Foam Applications

Between its sound insulative qualities and its ability to resist water, closed cell foam is ideal for applications like the following:

• Air security
• Ceilings
• Gasketing
• Insulation
• Mats
• Neoprene products
• Reinforcement for construction materials

Open Cell Foam Applications

Open cell foam is compatible with the above applications, as well. However, open cell foam achieves better air permeability, giving it additional applications in acoustic absorption and sound attenuation.

Acoustic Absorption

Two material options for open cell foam in acoustic absorption applications are polyether and polyester. Polyether foam is crafted from open cell polyurethane. Flexible and lightweight, this compressible foam offers impressive sound absorption as well as thermal insulation capabilities. Alternatively, polyester foam exhibits superior tensile strength.

Sound Attenuation

To reduce noise and noise pollution or dampen its transmission, open cell foam is a good choice for:

Cost Considerations

Compared to closed cell foam, open cell foam is significantly less expensive as it requires less plastic material to manufacture. This translates to lower costs while providing the same degree of thermal insulation through the effectiveness of its air permeability as an insulator. Although open cell foams are more cost-effective per cubic foot, closed cell alternatives are more successful at maintaining their performance capabilities over time. Just be aware that for installing closed cell foam, you may need specialized equipment.

Acoustic Absorbing Foam and More From Technicon Acoustics

To choose between open cell and closed cell foam, evaluate the specific needs and environment of your application. Open cell foam offers good sound absorption and attenuation as well as air permeability at a more economical price. Closed cell foam is durable and water-resistant for outdoor environments.

As a leading manufacturer of innovative products for acoustic and thermal applications, Technicon Acoustics, Inc. has been supplying OEMs throughout North America with custom solutions for over 40 years. Our team understands the key elements to designing sound enclosures and related goods, so we offer acoustic absorbers and barriers, vibration damping products, and an array of films, facings, and adhesives to meet the versatile needs of clients in industries ranging from air compressors and power generation to medical devices and specialty vehicles.

Offering a lead time of two weeks and a quality control rating of 99.91%, we strive to create the Perfect Order Experience for our customers. Contact us for help deciding between open cell and closed cell foam, or request a quote today on one of our many product options.

How Does Foam Absorb Sound?

Sound is simply vibration, moving through a medium such as air, that we can perceive with our sense of hearing. Those vibrations or waves are cycles of compression and rarefaction, rhythmically displacing the molecules of the medium between the sound source and the listener. These cycles, or frequencies, are louder or quieter depending on how much energy, or amplitude, the sound source inputs into the medium.

Sound pollution comes from many sources including heavy trucks and equipment, construction and industrial machinery, power generation operations, and more. It contributes to an uncomfortable or unpleasant work environment and can also reduce workers’ ability to communicate with each other or to hear equipment or vehicles, posing serious safety risks. One solution is to absorb unwanted sound vibrations with foam materials. Keep reading to learn more about how foams can be used to absorb sound.

How Does Foam Absorb Sound?

It’s important to understand that foam does not block sound; however, it can absorb it to varying degrees. Sound absorption improves acoustic quality in a space by reducing the sound you hear and by controlling echo and reverberation.

As sound waves interact with objects in their path, the object absorbs certain frequencies and reflects others, based on its material properties. The degree to which sound is absorbed at different frequencies is called the material’s sound absorption coefficient. It measures the ratio of absorbed sound energy versus that which is reflected. It is expressed with a value between 1 for total absorption and 0 for no absorption at all.

There are two primary mechanisms for how foam absorbs sound:

• Energy conversion, where vibratory energy is converted to heat.
• Trapped sound waves, where air pockets in the foam contain the sound, stopping it from reflecting into the environment.

The Role of Acoustic Foam’s Material Properties

Foam has different cell structures, which affect its permeability and airflow. There are two types of cell structures in acoustic foam: open cell and closed cell. Both feature a sponge-like, interconnected structural network, but as its name implies, open cells are open on all sides, while closed cells include at least some membranes that keep the cells sealed and separated. Open cells are more permeable, giving them a higher sound absorption coefficient.

Density and Thickness

The thickness and density of a foam material also affect sound absorption, particularly frequency response. Thicker, denser foam increases its acoustic impedance, which is a material’s opposition to sound waves of a particular frequency or frequency band. Thus, it’s important to match sound-absorbing foam to the offending frequencies.

Applications of Sound Absorbing Foam

Sound-absorbing foam has numerous real-world applications. In an industrial setting, excess noise and vibration can increase stress and interfere with communication, resulting in preventable safety risks. The mechanical vibrations can also disrupt sensitive electronics and other scientific instruments.

For these reasons and more, sound-absorbing foam is an effective solution for applications as broad as:

Sound Absorbing Foam from Technicon Acoustics

Technicon Acoustics continues to refine the science and application of sound absorption for a variety of industrial settings. Specially engineered foam is an effective solution for excess sound reverberation, improving comfort, safety, and equipment function.

We supply foam and other acoustic absorption products that work with a wide range of frequency spectra, and with varying degrees of absorbability. Contact us to learn more about our sound-absorbing foam products, or request a quote for help selecting a product for your application.

When to Consider Polyurethane Foam Alternatives

Sound absorption materials are integral components for minimizing noise pollution. Polyurethane foam is a preferred material for sound absorption, but its chemical composition and environmental impact have resulted in the development of more environmentally friendly alternatives. Here, we will explore several alternatives to polyurethane foam that offer effective sound absorption without having an adverse environmental impact.

Sound Absorption Polyurethane Foam Alternatives

There are several alternatives to polyurethane foam, offering high performance and reduced environmental impact. Here is a look at some common examples.

Polyester Fibers

Polyester fiber materials, including our PF-091 fiber blend products, offer various performance advantages over polyurethane foam. One primary advantage is its improved resistance to degradation. Polyurethane foam begins degrading from the point of its creation and degrades faster from exposure to humidity, heat, and UV light. Polyester fibers are inert, so they are resistant to these elements.

Polyester fiber can be used in heavy equipment applications due to its ability to be exposed to weather, extreme temperatures, and wash-down procedures. The stability of polyester fibers ensures they will not degrade in these extreme conditions.

While polyester fibers and polyurethane foam have a similar price point, the longevity and durability of polyester fiber sound absorption materials make them more cost-effective in the long run. The two materials also offer similar acoustic performance, but polyester fibers offer better performance for lower-frequency range sound absorption, which is ideal for diesel engine powered equipment. Polyester fibers are also effective for:

• Heavy trucks
• HVAC equipment
• Air compressors and pump enclosures
• Construction equipment
• Marine engine compartments
• Generator enclosures

Technicon Acoustics’ Polyurethane Foam Alternatives

PF-091 by Technicon Acoustics is a common alternative to polyurethane foam. This proprietary polyester fiber blend offers resistance to oils, fuels, and most chemicals, and can withstand temperatures reaching 350 °F. Available in thicknesses from 0.5 in. to 2 in., PF-091 can be fabricated to fit unique applications and features exceptional low-frequency sound absorption.

Factors to Consider When Choosing Polyurethane Foam Alternatives

When selecting an alternative product to replace your polyurethane foam, it is critical to consider several factors to ensure your solution offers the expected performance while delivering cost-effectiveness and sustainability.

Performance and Effectiveness

Sound absorption performance is a critical factor in assessing an alternative material to replace polyurethane foam. Consider whether the alternative materials offer comparable or enhanced capabilities for your application.

Environmental Impact

Many polyurethane foam alternatives are more environmentally friendly and sustainable. Ensure the product you select is sourced responsibly, recyclable, and reduces environmental impact to meet your sustainability goals.

Cost Considerations

Alternatives to polyurethane foam often have a higher initial investment. However, they can offer long-term savings through reduced environmental impact and energy efficiency benefits. Consider the entire cost of ownership to make an informed purchasing decision.

Polyurethane Foam Alternatives from Technicon Acoustics

Sound absorption is critical to many applications, including industrial machinery. While polyurethane foam is a common material for sound absorption, it has a significant negative impact on the environment. Alternative sustainable products offer similar or better performance with a reduced environmental impact, which contributes to a more sustainable future for all.

Technicon Acoustics delivers quality thermal and acoustic solutions for customers throughout North America. Take a moment to read more about our PF-091 HF-1 Blended Fiber to learn the benefits of selecting this polyurethane foam alternative. To learn more about designing effective sound enclosures, download our eBook, “Key Elements to Designing Sound Enclosures.” Contact us or request a quote to speak with a team member about your sound absorption needs.

What Is Sound Attenuation?

Excavators, bulldozers, and other types of heavy equipment can be very loud, posing certain hazards to operators, nearby workers and the surrounding environment. Sound attenuation materials can be added to this equipment to absorb sound or create a sound barrier, ensuring quieter and safer operation. But, what is sound attenuation, and how does it work? Keep reading to find out.

Understanding Sound Attenuation

Sound moves through the air in waves, losing energy over time. This reduction in the intensity of acoustic waves is known as attenuation. Sound attenuation can occur in numerous ways, including:

• Dissipating through the air when absorbed by another medium
• Reflected against a barrier
• Via interference from ambient noise

Because loud noises can pose certain safety hazards to workers, sound attenuation materials are often added to noisy equipment and machinery. These materials help to reduce sound waves, diminishing their volume and quality. The right sound attenuation solution requires careful consideration of numerous factors, including environmental conditions, distance from the sound source, material composition, and structural design.

Methods of Achieving Sound Attenuation

There are two main methods for attenuating sound in an environment:

• Soundproofing. Soundproofing stops noise from entering or exiting a space.
• Acoustic absorption. The main purpose of acoustic absorption is to reduce sound reflections within an area.

Achieving either of these attenuation methods requires specialized materials and technologies. Some of the most common sound attenuation products include insulation, air sealing and acoustic barriers.

Importance of Sound Attenuation in Different Environments

Having proper sound attenuation is critical across various industries. For example, the architecture and construction industries rely on quality sound attenuation materials to reduce noise pollution in residential areas, healthcare facilities, and various work environments. Other common applications of sound attenuation include:

• Automotive. Sound attenuation plays a key role in reducing road noise and improving the comfort of vehicles.
• Aerospace. In aircraft, sound attenuation materials ensure a peaceful cabin environment by reducing noise emissions from the engine.
• Entertainment. Sound attenuation ensures a comfortable, high-quality experience within various entertainment venues.

Sound attenuation has many other important benefits beyond mere comfort. Loud noises not only affect productivity but can also directly impact health. For this reason, there are several regulations in place that set specific standards for noise levels. Effective sound attenuation helps to comply with these standards while promoting better concentration and safeguarding public health.

Challenges and Limitations of Sound Attenuation

Although sound attenuation is very important, it poses certain challenges such as cost implications and limitations in blocking certain frequencies. However, technological advancements and ongoing research are leading the way to more innovative, effective, and high-quality attenuation materials and techniques. As this area continues to advance, sound attenuation solutions are predicted to include smart features and sustainable materials to address even more complex requirements.

Sound Attenuation in Industrial Machinery/Equipment

At Technicon Acoustics, we specialize in developing industrial noise control and sound attenuation products for a wide range of industrial equipment and machinery. Our products include:

• Acoustic Absorbers. These products prevent sound waves from reflecting off hard surfaces, thereby decreasing the level of airborne noise in a particular area. We offer both fiber-based and foam-based options.
• Acoustic Barriers. Our acoustic barriers are capable of blocking noise from transmitting from one space to another. These materials are typically made from mass loaded vinyl (MLV).

Sound attenuation products from Technicon can help control noise levels from various types of industrial equipment, including:

• Agricultural equipment
• Air compressors
• Articulated trucks
• Bulldozers
• Excavators
• Generators
• Off-highway trucks

Sound Attenuation With Technicon Acoustics

Sound attenuation plays an important role in creating safe, comfortable environments across various industries. At Technicon, we offer a range of sound attenuation solutions, including both acoustic absorbers and acoustic barriers. As a full-service manufacturer, we can provide fully customized products tailored to your unique specifications, all while ensuring accurate and on-time delivery.

For more information about our selection of sound attenuation products, contact us or request a quote today.

The Best Marine Noise Reduction Materials

Boat manufacturers need to use high-quality noise-reduction materials to improve boat quality, safety, and passenger comfort. A quieter environment on board is one of the significant factors potential customers consider when buying a boat, and many will pay to have the engine room as silent as possible.

Boat manufacturers use specialized marine noise reduction materials to create a more comfortable experience for passengers and crew. In particular, polyester fibers are more friendly to high-moisture marine environments and provide better noise reduction than traditional polyurethane foam.

Learn more about the best marine noise reduction materials, other noise reduction strategies, and the solutions available from Technicon Acoustics.

How Marine Noise Reduction Materials Affect Noise Pollution

Excessive noise from pleasure boats, custom yachts, and military craft disturbs those on board, on other watercraft, and on the shoreline. The National Association of State Boating Law Administrators (NASBLA) has set safe boating standards for acceptable noise levels to help deal with marine noise pollution.

The maximum sound level for boats with engines manufactured before 1993 should be at most 90 dBA, and the limit is 88 dBA for those manufactured after January 1, 1993. These noise levels should be tested per SAE J2005-Dec 91 while the boat is stationary at the dock. Additionally, no boat should operate with noise levels exceeding 75 dBA for shoreline users, per SAE J1970-Dec 91 standards.

To meet these standards for safe, comfortable operation, boaters need easy-to-apply noise reduction materials and processes.

Marine Noise Reduction Materials and Strategies

The following are some of the most common noise-reduction materials and strategies used on boats:

• Polyester Fiber: Polyester fiber dampens and minimizes sound transmission when applied inside box compartments. Lining the engine compartments or genset interior walls with polyester fiber composites significantly reduces the noise generated by this equipment. Polyester fiber works better than materials such as polyurethane foam due to its innate moisture wicking properties.
• Blocking the Direct Line of Sight to Noise Sources: Blocking the direct line of sight to noise, like engine compartment components, by using barriers or insulation materials between the passenger area and the compartment helps minimize the noise experienced by those on board.
• Treating as Close to the Noise Source as Possible: Applying noise-absorbing materials like polyester fiber close to the noise source, such as the engine or generator set, helps prevent sound from traveling throughout the boat.
• Design Best Practices: Boat designers should also incorporate noise reduction best practices in boat design from the beginning. This involves considering the placement of noise-generating equipment, optimizing insulation and materials, and designing compartments in a way that minimizes sound transmission. For example, vibration isolation mounts help ensure that the boat doesn’t vibrate with the engine. In addition to generator sets and engine rooms, hull structures and floors should also be treated with noise-reduction materials.

Marine Noise Reduction Materials from Technicon Acoustics

Technicon has an extensive catalog of materials to help with all aspects of noise reduction in boat building and marine applications. They include:

• Vibration-damping materials: We produce vibration-damping materials, including rubber, polyurethane, and polyvinyl chloride (PVC) sheets. Determining the perfect material depends on the specifics of the boat and the marine application.
• Acoustic barriers: We produce mass-loaded vinyl (MLV) acoustic barriers, also called sound barriers. These are dense, sound-absorbing panels that help reduce airborne sounds transmitted through floorboards, enclosures, and other spaces on a marine vessel.
• Acoustic absorbers: Acoustic absorbers prevent sound from reflecting off hard spaces such as engine enclosures and operator cabs, creating uncomfortable noise levels in the room. For marine equipment, we make acoustic absorbers made of a blend of polyester fibers, offering low-frequency absorption properties, thermal resistance, and UL94 HF1 compliance.

Every product in our catalog is suitable for boat building and other marine applications. Our polyester fibers do not degrade in high-humidity environments, unlike foam noise-reduction products.

Engine Room Treatments

In many cases the engine room is the original source for most of the noise problems generated in the marine envrionment. Therefore, there are a myriad of treatment methods employed to minimize the negative impact that this unwanted sound and vibration can have on your customers comfort. Technicon can assist you at this design phase in order to ensure that appropiate acoustical design elements are considered prior to any construction. This is often the most economical way to avoid have a noise problem.

Generator Set Treatments

Generator sets have many of the same sound sound features as the main engine and should be analyzed for treatment in much the same way. Even if the generator set is already located within treated engine rooms, it may be necessary to further treat the genset. Placing the genset in its own enclosure isolated from the hull structure and lined with the appropiate acoustical absorber or absorber/barrier composite is recommended.

Hull Structure Treatments

In many cases, despite exceptional work done to minimize engine room noise impact on the hull structure, the hull itselft by the virtue of its contact with the external environment can be a major source of noise problems. Secondary engine or shaft vibration, propeller caviation or even fluid dynamics can set up resonate modes in the hull that cause the entire boat to act as a giant surrounding sounding board or drum. The proper vibration damping materials applied strategically to the hull or deck can effectively dampen the resonate frequencies of the hull and minimize the noise problem and significantly improve passenger comfort.

Floor Underlayment Barriers

Noise transmitting from engine or generator rooms can be a significant noise source on boats. The addition of floor underlayment, made of closed cell foam with a vinyl acoustic barrier, is a simple but effective solution to managing sound levels inside the cabin. Floor underlayment is designed to reduce the amount of sound transmitted through materials, which dampens noise and/or blocks it from entering the cabin. Our acoustic floor underlayments are available in a variety of sizes and can be custom cut to fit the floor.

Get the Best Marine Noise Reduction Materials from Technicon Acoustics

Technicon Acoustics offers high-quality noise reduction materials and solutions, allowing boat manufacturers to reduce noise levels in boats to meet NASBLA’s safe boating standards. Contact us today to learn more about our marine noise reduction solutions. You can also request a quote for a project estimate, or explore our PF-091 Noise Reduction Materials.

Mass Law & Sound Transmission Loss

The mass law describes the relation between sound frequency, mass per unit area, and sound insulation efficacy. In other words, a material with a higher density is less likely to vibrate when in contact with sound waves and will transmit less noise through the substrate.

The sound transmission loss of a floor or wall differs depending on the structure’s method of assembly and the physical properties of the material, such as stiffness and mass. For example, in a double-layer wall consisting of wallboard on metal or wood framing, the sound transmission class (STC) can be critically affected by the following factors:

• Depth of air spaces
• The absence or presence of sound-absorbing material
• The extent of mechanical decoupling between the layers

Noise can be either blocked or absorbed, and mass law and sound transmission loss focus on blocking noise. When attempting to prevent noise transmission between rooms, the mass and weight of materials between them must be able to disrupt the transmission of sound waves through the structure. When comparing a 4 inch concrete wall of an industrial building to a standard 2×4 stud wall of a residential property, the wall with a higher mass will transmit less noise and naturally be quieter.

Learn more about the factors influencing sound transmission loss and the industrial applications of these acoustic concepts.

Factors Affecting Sound Transmission Loss

While residential applications vary considerably from industrial applications, the same logic applies. The most important physical property that controls airborne sound transmission through a structure or assembly is the mass per unit area of the component layers. The mass law equation states that when the mass per unit area of a single-layer wall or frequency doubles, the transmission loss will increase by approximately 6 decibels.

Since sound is directional in nature, we only need to strategically place noise barrier products in specific areas that are directly in the line of the noise. For example, in an excavator cab, we would only put a barrier on the wall between the engine and the cab, not around the entire space. This results in effective noise reduction as well as minimized material costs.

Mass-Law & Sound Transmission Loss: Industrial Applications

There is a misconception that doubling the mass of a material from 1 lb/sq ft to 2 lbs/sq ft pounds will result in two times the noise reduction. Mass law states otherwise.

At X frequency, a material performs at Y, resulting in an average STC rate. STC can help you compare different materials and products. Most typical 1 lb/sq ft materials have a 26 to 27 STC rating. According to mass law, if the material doubles in mass, its STC rating only increases by 6, meaning that 26 STC would only go up to 32 STC, resulting in only a 6 dB reduction in noise.

Cost vs. Performance Balance

While doubling materials can cost twice as much, it does not double the performance. However, adding a thin foam layer(decoupler) between the barrier layer and enclosure wall,will create an air gap between the materials. Separating the two structures increases performance according to the double wall effect, in which an air cavity exists between the barrier and the enclosure wall and will increase acoustic insulation properties.

Learn More About Mass Law With Technicon Acoustics

As a leading supplier for OEMs throughout North America, Technicon Acoustics specializes in developing noise control products for a wide variety of industries.

Contact us to learn more about our acoustic barriers, including floor mat barriers and mass-loaded vinyl materials, which offer exceptional noise absorption and sound transmission loss. You can also request a quote for your specific application.

What to Look For in Acoustic Absorbers

Acoustic absorbers are products that prevent sound waves from reflecting off of hard surfaces. Due to their ability to absorb and block sounds, they play an essential role in improving acoustics in many industrial contexts, particularly OEM equipment and enclosures. Acoustic absorbers help create safer, more productive spaces for living and working. This article will discuss the most important considerations when selecting an acoustic absorber for different applications.

General Considerations for Acoustic Absorbers

To identify the most suitable acoustic absorber for any given application, there are several key factors to consider:

• Acoustic absorption coefficient: This determines how much sound a given material is able to absorb. The higher the coefficient, the better the absorption. Expressed as a value between 0 and 1, an acoustic absorption coefficient of 0 indicates no sound is absorbed, while 1 means all sound is absorbed.
• Thickness and density: How thick and dense an absorber material is has a direct impact on its performance. Thicker, denser materials are able to absorb more sound.
• Material composition: The materials used in an acoustic absorber also have a big impact on its capabilities. Polyether foam and polyester foam absorbers are common soundproofing foams that can be customized according to thickness, facing, and other needs.
• Fire safety ratings: Ratings such as the ASTM E84 measure how quickly flames spread along a material’s surface. Fire-rated panels are categorized into classes, with class A indicating the highest resistance to spreading flames and the highest level of safety for occupants.
• Installation flexibility: Certain materials are more flexible and lightweight than others. The more flexible a product is, the easier it will be to integrate into an existing space.

Selecting the most suitable acoustic absorber for any application requires a basic understanding of these concepts, as well as knowledge of what sound frequency needs to be blocked. Low frequencies are more challenging to block (but humans are less sensitive to them) while high frequencies are more easily managed with a variety of foam-based products.

Acoustic Absorbers for Equipment

Equipment used in many industries can operate at dangerously loud noise levels. In these environments, acoustic absorbers ensure user safety and comfort. At Technicon Acoustics, we develop solutions for many types of equipment, including:

• Heavy-duty trucks: Cabs, engines, floor mats, transmissions
• Medical devices: Imaging and ultrasonic equipment, nebulizers, oxygen concentrators and generators, lab equipment
• Construction equipment: Articulated trucks, bulldozers, excavators, material handlers, off-highway vehicles
• Air compressors: Centrifugal air compressors, reciprocal air compressors, natural gas compressors, rotary screw air compressors, oil-free and oil-injected air compressors

Quality acoustic absorbers block or absorb sounds as well as reduce vibrations and improve the marketability and public perception of your products.

Acoustic Absorbers for Power Generation Equipment

In the power generation industry, acoustic absorbers mitigate noise emissions and create a more comfortable and safe working environment. Many types of power generation equipment produce harmfully high noise levels, including:

• Turbines
• Compressors
• Gensets
• Inverter generators
• Standby generators
• Portable generators

For all of these applications, Technicon Acoustics offers solutions that reduce noise levels by absorbing and dissipating sound energy. Our products are made from specialized materials that feature high acoustic absorption coefficients. They are designed to withstand the uniquely harsh operating environments of power generation equipment.

Incorporating acoustic absorbers into power generation equipment not only enables companies to comply with regulatory standards, but also protects worker well-being, minimizes noise pollution, and ensures good relations with surrounding communities.

Acoustic Absorbers for Automotive Applications

Whether used in mass transportation or heavy-duty trucks and specialty vehicles, acoustic absorbers ensure a comfortable driving experience. We offer automotive acoustic absorbers for many vehicle components, including:

• Floor mats
• Engine compartments
• Headliners
• Cabins
• Dashboard and door panels
• Trunks and cavities

Throughout these applications, acoustic absorbers create a quieter ride with reduced engine and road noise. They also minimize audio distortions, improve sound performance, and create a more immersive audio experience. No matter what challenges an automotive application entails, our experienced team can incorporate the right insulation product into your vehicle design.

Let Technicon Help You Choose the Right Acoustic Absorber

With the wide variety of acoustic absorber products available, identifying the best solution for your application is crucial. At Technicon Acoustics, we offer the solutions you need and tailor each product to your application’s requirements. Our team is always available to help you understand your options and select the most suitable acoustic absorber.

For more tips, download our free eBook, “Key Elements to Designing Sound Enclosures.” You can also contact us with any questions or request a quote.

Ways To Measure Industrial Equipment Sound Levels

A decibel (dB) is a unit of measurement measuring the intensity or loudness of sound. The unit of measurement was developed as a result of efforts to measure signal loss in telegraph and telephone lines. Bell Telephone Laboratories created the new unit of measurement in 1928, naming it the “bel” in recognition of communications innovator Alexander Graham Bell. Today, the unit is known as the decibel, a logarithmic expression of sound intensity.

Read on to learn why sound measurement is important and how to measure sound in industrial settings.

Importance of Sound Measurement

The decibel scale is logarithmic to better represent how our ears perceive changes in sound intensity. While dB represents unweighted sound pressure levels, dBA is A-weighted to better approximate human perception of the sound.

For high-frequency sounds, measurements for dBA are as high as those for dB. For example, the dB and dBA levels of a violin’s high-pitched E string are very similar. Lower-frequency sounds, however, will have a lower output level because they are processed by the ear less efficiently. So the lowest note on a tuba (16 Hz) will have a lower dBA reading than its dB level.

Even minor dBA increases can have a significant influence on hearing health. Human hearing is more likely to be harmed as dBA increases, and it can happen faster at higher volumes. The following conditions increase the risk of hearing damage:

• Exposure to 85 dBA for over 8 hours
• Exposure to 100 dBA for over 14 minutes
• Exposure to 110 dBA for over 2 minutes

A sound level meter can measure sounds in decibels, but it must be calibrated regularly to ensure consistently accurate readings. To ensure personnel safety, all readings taken by a sound level meter must be accurate and reliable.

Best Way to Measure Industrial Sound

Sound level meters are composed of four main parts: a microphone, an input amplifier, an output amplifier, and a readout device. The microphone turns fluctuating, sound-induced air pressure to a fluctuating electrical charge. The input amplifier then converts that electrical charge into a voltage, which the electrical circuitry processes to produce a sound pressure level (SPL). The output amplifier then converts the weak sound signal to a level suitable for display on the readout screen. Finally, the readout panel shows the typical sound pressure levels for the surroundings under consideration.

The meters can focus on particular frequencies within a larger soundscape using filters, which hone in on specific sound wave pressure bands. There are several types of sound level meters on the market with varying levels of versatility and precision. To measure industrial sound, you will need a more accurate meter.

Industrial Sound Solutions From Technicon Acoustics

Technicon Acoustics is North America’s leading acoustic and thermal solutions provider for OEMs. Our 85,000-square-foot facility is dedicated to producing advanced materials for your industrial applications. Contact us or request a quote today for more information on our products and capabilities.

Glossary

Technicon Acoustics, Inc. designs and manufactures customizable solutions for absorbing, isolating, and blocking acoustic and thermal energy. For your convenience, we have compiled a list of some of the industry’s most frequently used soundproofing and acoustical terms. Having a clear understanding of these terms will facilitate better communication during the product design process, ensuring a more individualized and optimized solution for your application.

Terminology

• Attenuation: Attenuation in reference to acoustics describes a frequency-dependent reduction in sound, or a sound’s diminished energy, as sound waves pass through a medium like absorptive urethane foam and glass fiber materials. To achieve attenuation, friction between air molecules and cellular or fibrous materials transforms that motion of molecules into thermal energy.
• Audiometry: Audiometry is the measurement of an individual’s hearing acuity for different sound intensities, pitches, or frequencies.
• Cutoff frequency: In reference to sound-absorbing foam wedges, or anechoic wedges, cutoff frequency describes the threshold frequency above which the normal-incidence sound absorption coefficient is no less than 0.990.
• Doppler effect: The Doppler effect describes the change in sound frequency as a sound source and observer move toward or away from one another.
• Extinction coefficient: The extinction coefficient, also known as the attenuation coefficient, is a measurement that indicates how strongly a substance absorbs or attenuates sound or light at a particular wavelength.
• Haas effect: The Haas effect, also known as the precedence effect, describes the phenomenon in which a human perceives two independent sounds as a single auditory event if they are separated by a sufficiently short delay (20-40 milliseconds).
• Human hearing range: In general, the audible spectrum of sound frequencies that humans can hear ranges from approximately 20 Hz to 20 kHz. However, this range can vary considerably between individuals and tends to gradually decline with age.
• Impact noise: Impact noise describes the sound that results from the vibrations of an object’s impact against a surface within a room. Those vibrations allow the sound to pass through the room’s structure. For example, in buildings, footsteps or dropped objects generate sounds that travel through the floor.
• Kerf or kerf cut: Kerf cuts are slits or notches at the edge of acoustical panels that allow for the insertion of a spline. The panel can then be connected to additional panels while maintaining a continuous, level surface at each joint.
• Mass-loaded vinyl: Mass-loaded vinyl is a heavy, high-density material that effectively blocks or contains sound waves. This flexible soundproofing solution can be applied directly to floors, walls, ceilings, and other surfaces to keep sounds confined within a space and minimize transmission.
• Noise floor: In reference to signal theory, identifying the noise floor means measuring the signal that results from the total sum of all sources of noise and background transmissions in a system. In this context, noise refers to all signals except that of the signal you’re monitoring.
• Sones rating: A sone is a unit of measure that describes the loudness of a sound as perceived by the human ear, where one sone is equivalent to approximately 1,000 Hz at 40 decibels over the typical reference level. Items like fans typically have sones ratings. For example, a bathroom fan with a sone rating of 0.5 is very quiet, while a 5 rating constitutes a loud fan.

Acoustic and Thermal Solutions from Technicon Acoustics

Using the latest manufacturing technology, Technicon Acoustics has the advanced capabilities and value-added services needed to create industry-leading parts for a range of soundproofing and thermal insulation applications. For more information, request a quote today or contact Technicon Acoustics at:

4412 Republic Court

Concord, NC 28027

704-788-1131