Category Archive: Acoustics and Noise Prevention

Thermal Insulation vs. Acoustic Insulation

When people talk about insulation, they’re referring to one of two types: thermal insulation or acoustic insulation. Thermal insulation materials reduce radiant and conductive heat. Common forms are foam insulation, reflective barriers, and blankets, which are found in both residential and industrial settings, where high-temperature insulation is critical for safe operations.

On the flip side, acoustic insulation materials absorb or block sound from loud equipment in the form of absorbers and barriers. They are found in industrial settings where there is noisy machinery as well as sound booths and other spaces where it’s essential to eliminate outside noises (or keep the inside noises from traveling out). 

Here we’ll discuss common types of insulation, insulation materials, and our patented solutions for both thermal and acoustic insulation.

Common Types of Thermal Insulation

thermal insulationThere are two main types of heat-resistant materials: insulation and heat reflection. Insulation keeps heat in a confined space, minimizing conductive and convective heat flow. An example of heat insulation is the puffy material in the walls of a residential building that prevents heat loss in cold weather.

Radiant materials reflect heat energy that travels in a straight line, such as heat from the sun. These materials usually line the underside of roofs to block sunlight and reduce heat gain. Radiant materials keep buildings cool in hot climates.

Depending on the application, you will need different types of heat protection materials. All of the following require proper safety precautions during installation, but they are highly effective for insulating, reflecting, or both:

  • Mineral wool. Mineral wool can refer to glass wool, basalt rockwool, or slag wool. Most mineral wool in the United States is slag wool, and it comes either loose or in batts. Mineral wool is inexpensive and effective at insulating heat.
  • Fiberglass. Fiberglass can insulate or reflect heat. It is highly effective, but like mineral wool, it is hazardous if the glass particles are inhaled or enter the eyes.
  • Polyurethane foam. This insulating material is soft, flexible, lightweight, fire-resistant, and moisture-resistant.
  • Ceramic fibers. Ceramic fibers can either insulate or reflect, and they are most commonly used in heavy-duty industrial applications because of their high resistance to thermal shock. Common applications include exhaust systems, kiln linings, pipes, fire protection, seals, and expansion joints.

Common Types of Acoustic Insulation

Absorber Foam by Technicon AcousticsAcoustic insulation comes in two main types: absorbers and barriers. 

Absorbers

Absorbers take in and trap sound waves, which reduces the amount of noise in a space and improves acoustic conditions. They may be applied to walls, ceilings, floors, and even objects within a room.

Barriers

An acoustic barrier is used to block noise from transmitting from one location to another. Typically used in conjunction with absorbers, barriers are common in soundproofing applications like engine housings, firewalls, and more. The substrates used to make barriers are denser than those used for absorbers, and while absorbers receive a Noise Reduction Coefficient (NRC) rating that indicates how much sound they can absorb, barriers receive a Sound Transmission Class (STC) rating, which indicates how well they block sound. 

There are many types of acoustic insulation materials available, and they all do a great job at redirecting or absorbing sound. The one you choose will depend upon your budget, your application, any restrictions regarding the size and weight of the chosen material, and the NRC or STC rating you require.

Common types of acoustic insulation materials include: 

Sound Absorption Materials

  • Fiberglass. Long-lasting and fireproof, fiberglass offers both thermal and acoustic insulation. 
  • Polyester Non-woven Fibers. Safe and stable, polyester offers flexibility and durability at an economical price point. 
  • Polyurethane Foam. This is an excellent choice for absorbing high-frequency sound waves. 
  • Rockwool. Moisture- and fire-resistant, rockwool is easy to cut and fit, and it offers more sound absorption than traditional fiberglass. 

Sound Barrier Materials

  • Concrete. It’s not the most effective, but it is versatile and durable, which is why it’s used for about half of all highway noise barriers made in the U.S. 
  • Steel. It’s inexpensive and easy to work with, making it a common choice for sound barriers. 
  • Acrylic. Though more expensive than other choices, acrylic is necessary when you want to create a transparent barrier to avoid blocking the view. 
  • PVC and other viscoelastic materials. These are cost-effective options for sound barriers for a wide variety of applications. 

Thermal Insulation Benefits 

Thermal insulation is great for protecting products, devices, ancillary items, and people from a nearby heat source. Here, we’ll break down several specific benefits of thermal insulation as they relate to specific applications.

  • Hotspot prevention. Motors and other equipment can create high-temperature areas which can damage nearby electronics, other sensitive equipment, and people. Hotspot prevention is crucial to protecting these assets.
  • Fuel tank protection. Thermal insulation helps control fuel tank temperatures, reduces safety hazards, and is extremely important in protecting plastic fuel tanks from melting.
  • Surface temperature reduction. Certain kinds of equipment can become extremely hot in the process of running, so thermal insulation is critical in preventing burns by way of being a non-conductive barrier between people and the machinery.
  • Exhaust pipe protection. Exhaust pipes produce a sufficient amount of heat. Insulation protects internal components from heat-related damage while also regulating internal temperatures.

Acoustic Insulation Benefits

Acoustic insulation’s benefits revolve around noise reduction for a healthier workplace, but to fully understand the specific benefits, we’ll take a closer look. 

  • Sound absorption. Porous absorption materials are used to line the surfaces of hard objects (e.x. Heavy machinery, engines), which would typically reflect sound and airborne noises into a workspace. The porous materials keep sound waves from reflecting back into the workspace which promotes worker health. 

Thermal Products by Technicon

Technicon Acoustics offers several high-temperature thermal insulation materials that are safe and effective for a broad range of applications. 

Our Tech Shield™ is a hazard-free radiant solution that enhances comfort inside operator environments and cabins. It blocks heat sources up to 1000 °F as close as one inch away. With a fire-retardant core and low setup costs, Tech Shield™ ensures the safest and most efficient means of heat protection. 

Our Tech Shield Sleeve™ is a braided sleeve composed of patented fibers that insulate exhausts, keeping the heat in and lowering surface temperatures. It comes with special structural cords that cure the sleeve in place after initial exposure to heat. Once cured, the sleeve does not unravel even if the sleeve gets damaged or the pipe moves.

Acoustic Foam Products by Technicon

We produce three types of acoustic foams (otherwise called soundproof foams) which are used to manufacture acoustic absorbers. These materials are available in various thicknesses and facing options, and they may be used alongside sound barriers for additional noise control. 

  • Polyether & Polyester Polyurethane foam. It’s lightweight, flexible, compressible, and thermally insulating, in addition to offering exceptional sound absorption. 
  • Fiber-based absorbers. These offer an environmentally-friendly alternative to polyurethane. Made of our proprietary blend of virgin fibers with pre- and post-consumer waste, these absorbers are recyclable. They won’t degrade with exposure to UV light or water, and they’re resistant to most chemicals and oils. With exceptional low-frequency absorption properties, thermal resistance up to 350° F, and compliance with UL94 HF1 standards, fiber-based acoustic absorbers are a common choice in generator and air compressor enclosures, marine engine rooms, and HVAC applications. 

Technicon: Superior Thermal and Acoustic Solutions 

At Technicon, our experts develop high-performance thermal and acoustic solutions for original equipment manufacturers (OEMs) across the United States and Canada. We are committed to providing clients with products that meet their exact specifications. We also take care that our deliveries are on time and accurate. 

To learn more about our thermal insulation, radiant blocking solutions, or any of our acoustic solutions, request a free quote or contact us today.

Why OEMs Prefer Our Exhaust Wrap Over Traditional Sleeves

Whether working with anything from exhaust systems to heavy industrial equipment, exhaust wraps serve as multipurpose insulating optionWhile a broad variety of thermal insulating blankets and covers remain on the market, they lack the versatility of Technicon’s Tech Shield Sleeve exhaust wrap.  

Critical to original equipment manufacturers (OEMs) working within a broad range of industries, well-fitted exhaust insulation ensures optimal equipment operation. This diverse range of industries includes construction, agriculture, transportation, and automotive, and so the experts at Technicon understand the importance insulating options that can easily adjust to fit a wide variety of sizes and configurations. 

Exhaust Sleeve vs Exhaust Blanket Infographic

Click to Expand

Our Thermal Exhaust Wrap vs Traditional Sleeves 

Technicon’s Tech Shield Sleeve thermal exhaust pipe wrap provides a broad range of advantages over traditional sleeves. Our products prove particularly useful for unique OEM equipment with easy installation, superior heat resistance, lightweight materials, better fit, and enhanced user safety.   

Quick and Easy Installation 

Unlike traditional sleeves, our Tech Shield Sleeve thermal exhaust wrap comes easy to install and fitted to suit the shape of your pipe or conduit. Simply slip the wrap around the pipe and clamp the ends to secure the cover. While traditional sleeves demand particular positioning and must be secured with numerous fasteners, Tech Shield Sleeve is expected to be 25-30% faster to install at minimum, according to an internal study. 

Heat Resistance 

Traditional fiberglass insulation products can only withstand up to 600 °F, at which point they begin to clump and deteriorate. However, Tech Shield Sleeve exhaust insulation wrap performs ideally for operating temperatures up to 1500 °F. With high quality insulation able to withstand these extreme temperaturesexhaust products can then undergo intensive particulate filtration in order to meet emissions requirements. Additionally, our Tech Shield Sleeve exhibits exceptional temperature drop and consistently passes a rigorous internal gas temperature drop test conducted by a major Fortune 500 manufacturer of engines for automotive and heavy equipment. 

Lighter 

Up to 40% lighter than traditional sewn insulating wraps, Tech Shield Sleeve offers the same coverage and protection, but lightweight construction makes our product easier to install. These lighter properties make them ideal for use in weight-sensitive equipment in the automotive and aerospace industries, where even a small amount of added weight can significantly affect operational efficiency. 

Better Fit. Better Look. 

Designed to fit tightly, Tech Shield Sleeve prevents the intrusion of debris and dust that could compromise equipment performance. Unlike sewn wraps that must be stringently designed, our one-size design accommodates a broad range of pipe diameters while still maintaining a reliable fit. The adjustable design of our exhaust heat wrap allows us to offer fewer SKUs to fit a wider range of pipes and exhaust systems. This adaptability saves OEMs time and money otherwise spent on exhaustive prototyping and custom sewing for each product design. Furthermore, our sleek, fitted design also provides a more professional, highperformance aesthetic than traditional sewn heat wraps. 

Safer 

Our Tech Shield Sleeve provides adequate coverage for any dangerously hot equipmentensuring the safety and health of equipment operators. Unlike more traditional fiberglass products, our superior design materials make Tech Shield Sleeve less irritating to the skin and eyes, and our fitted design and superior temperature drop ensures a more comfortable work area.  

Exhaust Wrap Applications 

OEM equipment often presents challenges with unusually shaped pipes, valves, and other components which require innovative insulation solutions. Nevertheless, Technicon’s knowledgeable experts can help you find the perfect heat wrap for your exhaust system. We specialize in the design and manufacture of thermal insulation wraps for numerous industries, including: 

Exhaust Wrap Solutions by Technicon Acoustics 

At Technicon Acoustics, we take pride in designing, developing, manufacturing, and delivering acoustic and thermal insulating solutions for OEMs across the United States. Our dedicated team of engineers, manufacturing specialists, and administrators use cutting-edge technology and state-of-the-art equipment to produce the perfect insulating products for your needs. We strive to meet and exceed your expectations by delivering superior insulation solutions in a timely and cost-effective fashion.    

To learn more about ways that Technicon Acoustics can revolutionize your operation, contact us today or request a quote.  

Acoustic Components in the Medical Industry 

Patients and medical practitioners both benefit from quieter environments, but hospitals and laboratories often have high levels of ambient noise. Even clinics, offices of private practitioners, and homes of recuperating or long-term patients still have noises that may cause distraction or anxiety.

Acoustic-Components-in-the-Medical-Industry

Noise absorbers and sound dampening materials are important throughout the medical industry as patients and medical professionals seek to reduce noise levelsOEMs are often asked to reduce noise levels on equipment such as: 

  • Diagnostic and testing equipment 
  • Home-use medical devices 
  • Hospital-based care equipment 
  • Patient care equipment

reduce noise levels medical equipment

Medical Environments That Require Sound Absorption 

Good medical acoustic design involves balancing competing interests. Enclosed devices can have more sound-muffling technology, but visible controls facilitate easier use. Sound-absorbing outer shells might make equipment maintenance harder even as they quiet the noise level. Striking the right balance between these factors can dramatically increase the comfort and usability of medical equipment. 

Medical Environments Require Sound Absorption

Some of the specific benefits of good acoustical design include: 

Patient Satisfaction 

Noisy settings can be stressful and displeasingThis negative impression can impact a patient’s decision to choose your facility and their perceived quality of care. 

Better Employee Focus and Productivity  

Loudunusually low-pitched or high-pitched, and/or repetitive noise(often referred to as tones) can distract employees. Adverse acoustic conditions can also impede clear communication or cause doctors, nurses, and medical staff additional stress in what may already be a stressful work environment 

Removing or minimizing ambient noise and tonality in equipment can improve employee performance by reducing the risk of error, improving communication between staff and patients, and improving employee satisfaction with their workplace. It may also reduce HIPAA violations and better protect patient privacy because staff can speak more quietly.  

Improved Health for Everyone in Contact with the Acoustical Environment 

Adverse acoustical conditions have negative physiological ramifications. Reducing exposure to loudgrating, or repetitive sounds can help patients heal and can be a crucial part of promoting a healing environment. Quieter work conditions also reduce stress, headaches, and anxiety. 

Solutions Design for Acoustics in Healthcare Environments 

Sound Design for Acoustics in Healthcare Environments

Choosing the right acoustical components for a medical application is essential. Sound technicians can add acoustic insulation behind exterior covers to dampen internal vibrations and noise pollution caused by medical equipment. While the external covers protect the internal machinery from contamination, air exposure, and damage, the covers also provide the right surface area to install acoustical absorbers. Large equipment such as blood analyzers, magnetic resonance imaging (MRI) chambers, and oxygen concentrators can all benefit from acoustic insulation without suffering any loss of performance. 

The search for high-quality acoustical components is not the only important factor to take into consideration, but finding the correct manufacturers is vital as well. You do not just need a solution that absorbs, blocks, and isolates sound, but you need solutions designed and developed by a manufacturer to match every specification. The quality of these solutions is only as superior as its manufacturer.

patient specific health benefits

This is especially important for medical equipment that continuously runs near patients. Patients staying in the hospital overnight or for long periods of treatment need to have calm, quiet conditions. Reducing ambient noise levels by insulating the nearby operating machinery creates patient-specific health benefits such as: 

  • Better sleep 
  • Improved general safety 
  • Superior quality of communication 
  • Lowered blood pressure 
  • Reduced stress and anxiety 
  • Less demands for pain medication  

Does Your Equipment Require Noise Reduction? 

Most medical environments can benefit from noise reduction technology. These locations become safer and more hospitable for both patients and medical professionals when there is less noise and vibration.  

Does Your Equipment Requite Noise Reduction

At Technicon Acoustics, we’re here to help with all of your sound control needs. We offer the following healthcare acoustic control products: 

Acoustic Absorbers 

Once sound leaves a device, it becomes airborne. Our acoustic absorbers muffle this airborne noise by absorbing the soundwaves. We produce porous acoustic foamsalso known as sound-proof or sound-absorbing foam. This foam comes in a variety of thicknesses and facings.  

Our team can customize acoustic absorbing layers to target the specific frequencies of the noise pollution in your applicationBy adding this material to surfaces that can reflect sound, you can control the total ambient noise within a space. 

Acoustic Barriers 

While acoustic absorbers control noise within a given space, acoustic barriers contain the sound so it doesn’t spread in the first place. We’ve carefully designed our barriers to stop the transmission of soundwaves. By using acoustic decouplerswhich interrupt the transfer of the sound through mediaand acoustic absorbers, you can control sound in and out of specific areas. We can also design our barriers with composite materials that perform all of these functions simultaneously.  

Sound Control Solutions from Technicon Acoustics 

Sound control solutions from Technicon Acoustics

If your medical facility is too loud or the sound of the onsite equipment is interfering with patient and employee health, contact us todayor request a quotefor help creating custom noise reduction solution that perfectly fit your environment. 

Why Is Noise Reduction Necessary in Construction Equipment?

According to a study performed by the American Industrial Hygiene Association in the early 2000s, over 500,000 construction workers are exposed to noise levels that pose a potential risk to their auditory health and well-being. In addition to affecting the working conditions for these workers, the sound produced at construction worksites affects the living quality of the surrounding communities and environments. One of the most significant contributors to these elevated noise levels is the construction equipment employed, such as excavators and bulldozers.

Escavator

By implementing noise reduction measures—such as damping foam, acoustic absorbers, and acoustic barriers—in construction equipment, industry professionals may not entirely eliminate noise pollution, but they can reduce sound to more tolerable levels. While these materials are available as aftermarket products, it is much more efficient for original equipment manufacturers (OEMs) of construction equipment to keep in mind acoustic design—including noise reduction—when developing and constructing their products from the beginning.

At Technicon Acoustics, we have the industry experience and knowledge to deliver high-quality equipment noise reduction and soundproofing solutions to OEMs. By bringing the noise produced by their equipment to more acceptable levels—minimizing the impact on machine operators and the surrounding environment—we improve the marketability of their products, enhance consumer perception, and facilitate compliance with regulatory standards.

Benefits of Noise Reduction in Construction Equipment

The integration of noise reduction and soundproofing components in construction equipment translates to significant benefits in the workplace. For example, lower noise levels in construction worksites can lead to:

  • Greater concentration and better communication. Reducing the amount of sound generated by construction equipment enables workers to concentrate and focus on the task at hand without being distracted by equipment noises. Additionally, it facilitates better communication between individual workers during collaborative tasks and/or potentially hazardous situations.
  • Lower rates of error and injury. The greater concentration and better communication achieved in quieter worksites also result in a lower risk of worker error and injury.
  • Reduced worker stress. Sound significantly affects a construction worker’s physical and mental health. Elevated noise levels can lead to hearing loss and other ear-related issues as well as cause emotional stress that results in diminished worker productivity. Lower noise levels in the worksite alleviates these concerns.

Construction equipment that facilitates these benefits are more appealing to consumers, so it is in the best interest of OEMs to integrate such acoustical solutions in their equipment.

Using Technicon Products to Reduce Noise

At Technicon Acoustics, we provide a variety of products to help customers manage the noise produced by their equipment in economical ways, including:

  • Vibration damping, for reducing noise from vibrating metal panels. Panels can be treated with our materials to disrupt the resonant frequency, reduce secondary sound generation, and limit structural vibration. Damping material is extremely light and effective, allowing for the reduction of noise without adding too much weight to the equipment’s components.
  • Acoustic absorbers (Product: Polyether Foam AF-021), commonly used for unwanted noise in engine compartments, this reduces airborne noise by absorbing the sound waves.
  • Acoustic barriers, blocking noise transmission. While absorbers reduce the amount of sound reflecting off a hard surface and spreading through the air, barriers stop sound waves from getting through the material to the other side of an equipment enclosure. Barrier composites are crucial for machine operators as they are placed around the base of control levers to block sound leaks and prevent them from reaching the cab.

Partnering With Technicon Acoustics for Noise Reduction

At Technicon Acoustics, we produce solutions for sound reduction and thermal transmission problems. We work with original equipment manufacturers across North America to design, develop, and deliver products that protect consumers from excessive noise and heat transmission.

For additional information about noise reduction, download our Heavy Equipment Acoustical Treatment eBook. If you need help reducing noise in your new and existing equipment lines, request a quote today.

Acoustic Solutions to Portable and Standby Power Generators

A dangerous, yet easily overlooked problem in the power generation industry is the noise produced by standby and portable generators and turbines. This type of equipment can produce excessive amounts of noise and heat, eventually causing damage to the surrounding area, reducing the lifespan of the equipment, and creating an unsafe working environment. Acoustic enclosures offer an ideal solution to counteract these problems, along with improving customer acceptance and marketability.

Fluid, Air and Pump Treatment Guide

Equipment That Requires Sound Absorption

The severity of noise pollution created by generators can vary depending on a number of factors. Motor size, the type of exhaust system, and the style of radiator fan installed can all impact the level of sound put out by a generator. Standby generators can produce noise up to 80  decibels or above, causing damage to equipment over time and posing potential health and safety risks for operators.

While the intensity of sound can vary depending on the generator, the causes of the sound are generally the same on most power generation equipment. These sources include:

  • Engine noise
  • Engine exhaust
  • Turbulent airflow caused by cooling fans
  • Alternator noise

Sound may be dampened considerably on power generation equipment by creating a weighted barrier to line the sheet metal enclosure of the generator. A decoupled weighted barrier may also be used for generator noise reduction, which involves the addition of decoupling foam to the barrier before installation.

To ensure that power generation equipment continues working safely and effectively, it is important to provide several openings in a generator sound enclosure for heat and exhaust to be released. These openings also enable air flow to the machine. If heat isn’t properly released, it will eventually damage equipment.

While these openings are vital for the functionality of your equipment, they reduce the efficacy of the barriers by allowing some of the sound waves to escape. To absorb sound that can’t be controlled with sound dampening liners, operators can incorporate acoustic absorbers as a lining for louvers or to create a tortuous path for airflow to absorb the noise before it escapes.

Solutions for Portable and Standby Generators

Acoustic control systems for portable or standby generators come in a variety of different types of material. They are built out of composite layers of foam, vinyl, and fiber and work by blocking, deflecting, or dampening the sound waves being created by the generator. This generator soundproofing material protects the workspace and ensures the longevity of equipment. These treatments are straightforward and easy to install. Typically, they are flexible and come with an adhesive that simply requires sticking them in the right place.

Request Your Custom Noise Pollution Solution Today

Technicon Acoustics is dedicated to helping solve your noise pollution problems. We’re involved in the process every step of the way—we design, develop, manufacture, and deliver every single part you need. Our products are specifically designed to isolate sound and thermal energy, and to absorb or block the vibrations that cause damage and noise pollution. We can customize our solutions to specifically target the sound frequencies impacting your operation.

Our team is made up of engineering, manufacturing, and administrative professionals who combine their expertise to make sure every one of your expectations is met and exceeded. We make use of the most up-to-date technologies and industry knowledge, and do all of our work in a modern, state-of-the-art facility. To find out more about how we can provide you with custom solutions, request a quote today.

 

The Importance of Acoustic Enclosure Treatments

Loud noises are not just distracting or uncomfortable for workers—they pose serious safety risks that lead to hearing loss. Reducing noise with acoustic enclosure treatments is an important element in creating a healthy work environment and facilitating employee productivity. These enclosures reliably reduce, minimize, or eliminate noise from specific sources in countless industrial environments.

Benefits of Acoustic Enclosures for Noise Reduction

Industrial machinery often exceeds allowable noise levels, but acoustic enclosures used in industrial environments facilitate noise reduction in compliance with federal, state, and local statutory limits. Noise enclosure treatments provide a number of benefits, including:

  • Measurable noise reduction, from 15dB(A) to 50dB(A)
  • Noise reduction for air inlet drive on combustion engines
  • Acoustic level reduction of combustion engine exhaust removal
  • Availability for indoor or outdoor applications

Applications for Acoustic Enclosures

Acoustic enclosures are present in a variety of facilities across a broad range of industries, applying noise reduction or elimination solutions to common noise pollution issues. Some examples include:

Mobile electric power generator for emergency situations.

Outdoor Generator Enclosures

Outdoor generator enclosures reduce damaging frequencies from continuous engine noise. Though many portable generators integrate adequate levels of sound reduction, most industrial generators produce noise levels well in excess of OSHA’s permissible exposure limit (PEL). OSHA currently allows 90dB over a period of eight hours and only two hours of exposure to 100dB.

Transformer Enclosures

While transformers may not generate loud or intense noise, they do produce noise at a continuously damaging frequency. Transformer enclosures minimize the continuous humming and high-frequency noises commonly associated with this equipment.

Noise Reduction Solutions from Technicon Acoustics

Technicon Acoustics is an industry leader in the production of acoustic solutions for original equipment manufacturers throughout North America. We design, develop, manufacture, and deliver components and materials that block, absorb, and/or isolate acoustic and thermal energy. We incorporate the most advanced materials, systems, processes, and technologies within our state-of-the-art facility in order to meet or exceed the expectations of our customers.

Our customers rely on us to provide adequate acoustic absorption materials and noise isolation in a broad range of industries and applications, such as:

Contact us for more information about the acoustic enclosure treatment solutions provided by Technicon Acoustics or request a quote from one of our acoustics experts.

Acoustical Treatments for Air Compressors

Air compressors are an efficient means used to fill gas cylinders with high pressure air, power HVAC control systems and pneumatic tools, and a broad range of other mechanical functions. Their biggest drawback is their noise level, which reaches between 70 and 90 dB depending on their rotational frequency, system design, and flow factor. 

To control the amount of noise generated by air compressors, industrial facilities employ a few different methods, such as: 

  • Containing the sound energy by forming sound barriers and enclosures for the machine
  • Damping the noise-causing vibrations
  • Dissipating the sound energy through various means of sound absorption

Enclosures & Sound Barriers

One method of minimizing air compressor noise is to isolate the device within a sound barrier, which reduces the amount of airborne sound transmitted through walls, floors, and ceilings. The most common material used for this purpose is mass loaded vinyl (MLV). Although MLV is heavy, it is not very thick, making it a viable solution that does not take up a lot of space. 

Typical applications for sound barriers include:

  • Bulkheads
  • Cab floors
  • Engine compartments
  • Firewalls
  • Machine enclosures
  • Pipe wraps

Studies focused on attenuating radiated compressor noise concluded that sound absorptive material by itself is ineffective in dealing with frequencies produced by large reciprocating air compressors between 63 Hz and 125 Hz. However, installing an enclosure component with acoustical absorptive lining around the intake sufficiently reduces the sound energy through wave reflection and cancellation.

Vibration Damping

One of the primary sources of air compressor noise is vibration. Although most air compressors are equipped with rubber feet to provide vibration damping, the wear from long term use and their overall inefficiency make them largely ineffective. 

Employing vibration damping material, such as constrained layer damping (CLD), diminishes the amount of airborne and structure-borne noise produced by decoupling the air compressor from its installation floor or base. The material also reduces the amount of vibration experienced throughout the system, increasing the overall machine stability.

Some of the equipment for which vibration dampers are commonly used include:

  • Door and floor panels
  • Enclosure cabinets
  • Fuel tanks
  • Wheel wells

Sound Absorption

Sound absorbers are porous materials available in foam or viscoelastic fiber forms. Applying these acoustic materials to hard surfaces allows for the absorption—rather than the reflection—of sound, decreasing the amount of airborne noise depending on the type of absorber material. For example, in one case study, wrapping acoustic absorbers made of mineral wool around components or using it to line an enclosure provided an overall noise reduction of 25 dB. The thickness of the acoustic absorbing material employed also influences the level of sound reduction achieved. 

Common uses of sound absorbers include:

  • Engine compartments
  • Home appliances
  • Machine enclosures (e.g., for generators, water pumps, and air compressors)
  • Medical equipment
  • Truck and heavy equipment cabs

When choosing a sound absorption material for your air compressor, it is important to keep in mind potential interactions between your equipment and the material. For gas and electric compressors, specialized materials are available with additional properties, such as adhesive backings and chemical resistance, to prevent undesirable material-machine interactions. 

Contact Technicon Acoustics Today

Air compressor noise presents a significant problem in the workplace. However, there are several methods of reducing the amount of noise produced by a facility’s equipment, including using sound barriers and enclosures, vibration dampers, and/or acoustic absorbers. 

At Technicon Acoustics, we provide a range of noise reduction products that employ all three of these methods. To learn more about our range of acoustical treatment solutions for air compressors, contact us, or request a quote from one of our experts.

The Cost of Noise

On average the CDC reports that in 2007, “82% of the cases involving occupational hearing loss were reported among workers in the manufacturing sector” Hearing Loss is the most commonly recorded occupational illness in Manufacturing accounting for 1 in 9 recordable illnesses. It’s estimated, that there are 16 million people working in the Manufacturing Sector, which accounts for approx 13% if the US workforce.

Hearing loss disability results in an estimated $242 million dollars worth of workers compensation payments each year. According to hear-it.org. As many as 95% of construction workers are exposed to high levels of noise on a daily basis. When left untreated, hearing loss can reduce earnings by as much as $30,000 a year. The top industries that have the most hearing loss claims? Construction, Carpentry, Farmers, and Mining resulting in 30 million work-related injuries each year. The machines that caused the most noise are Jackhammers, Dump trucks, Cement Mixers, Electric Saws. Plant work and Power Stations resulted in 100 DBA ( A-weighted decibels) with Sewer water and Residential Construction sites following behind between 93-99 DBA. *see how to measure noise on a construction site*

Most will argue that the primary cause for the hearing loss injuries in Manufacturing, Construction, Mining etc is that there’s a lack of educational training on how to prevent Occupational Hearing Loss. According to Mr. Neitzel’s report:

“Occupational health regulations governing the construction industry, including those pertaining to hearing conservation, are generally less comprehensive than those for the general industry. As a result, health surveillance and prevention programs for chronic diseases such as NIHL are limited in the industry. The US Occupational Safety and Health Administration (OSHA) has two regulations pertaining to hearing conservation in the construction industry. The first… set forth an eight-hour time-weighted average (TWA) permissible exposure limit of 90 dB, and requires a hearing conservation program (HCP) for workers whose exposures exceed this level. The second, [regulation] requires the use of hearing protection devices (HPDs) when noise exposures cannot be reduced below the Permissible Hearing Levels PEL.”

Source: healthyhearing.com

See the Story on how poor acoustics affects farmers Source: National Geographic

How to solve it

Marine

Whatever kind of boat you build, your customers will appreciate your efforts to make it quieter. Engine noise, prop cavitations, shaft whirl, all generate noise and create a vibration that can be controlled with the right noise control materials. Here’s our recommendation for a 47″ Trawler Yacht.

  • Engine Room – Use Absorber/Barrier composites. The absorber layer reduces reverberant noise. The barrier layer reduces sound transmission from the engine compartment.
  • Bulkheads – Here, you can also use an absorber and barrier. Either separately or in a composite to reduce reverberant noise and block sound.
  • Hull Structure – Treat hull and deck vibration with proper damping materials.

How to measure reverberant noise

Transportation

Operators of Transportation products such as trucks, buses, trains and emergency vehicles spend their entire day in the vehicle. The major noise sources in a vehicle are the engine, accessories, road and wind noise. Noise can enter the operator and passenger compartments by a variety of paths – through the glass, dash, floor doors etc.

  • Flooring Systems – Road Noise is generated by the vehicles passage over the highway surface and resulting tire and air noise. By using a Barrier Composite you can reduce the impact of road noise on the operator and its passengers.
  • Body Panels – Large surfaces such as floor pans and door panels are prone to vibration. Typically, the greater the surface the greater the noise. Vibration damping materials applied to these surfaces reduce vibration – radiated noise.
  • Hood Liners -These can be manufactured to act both sound absorbers and Heat Shields. They can reduce the reverberant engine noise thus improving both the outdoor environment and the cab interior. They can be made with a protective, heat-resistant facing and sound-absorbent material.

Heavy Equipment

Major noise sources in heavy equipment are the engine, drive train and power take-off systems. The sound radiates throughout the environment and affects operators, bystanders, nearby businesses and individuals.

Read the blog: Tuning into Urban Noise

  • Operator’s Cab- Headliners and sidewall trim systems that incorporate sound absorbers and sound barriers can be used to block sound entering the operator’s compartment and absorb sound reflection from within the operator’s cab. (Contact us to see which facings can be used for functional and aesthetic purposes.
  • Firewall and floormat systems- Firewall composites block sound from the engine and drive train and prevent noise from entering the cab. These can be manufactured either with or without a heat shield component. Sound barriers bounded to a durable wear surface create floormats that reduce sound transmission and improve operator comfort.

Technicon Acoustics did a case study on measuring and decreasing noise in the cab of a motor grader. Click here to see the results

Contact Us

See our list of Solutions and Capabilities at www.techniconacoustics.com and request a consultation with our Sound Solution Sales Team.

Our Favorite TED Talks about Sound and Noise

Harnessing the power of sound

Humans are wired for sound. Steve Keller, one of the world’s leading experts in the field of audio branding, explores how brands are harnessing the power of sound and music to shape our perception and influence our behavior, ultimately asking the question: How can we use these same strategies and
tactics to make our world a better place?

The 4 ways sound affects us

Playing sound effects both pleasant and awful, Julian Treasure shows how sound affects us in four significant ways. Listen carefully for a shocking fact about noisy open-plan offices.

 

Tinnitus Ringing of the Brain

In this talk, Josef Rauschecker illuminates the science behind tinnitus as well as the current state of treatment options.

 

SShhh! Sound Health In 8 Steps

Julian Treasure says our increasingly noisy world is gnawing away at our mental health — even costing lives. He lays out an 8-step plan to soften this sonic assault (starting with those cheap earbuds) and restore our relationship with sound.

 

 

 

Why Architects need to use their ears

Because of poor acoustics, students in classrooms miss 50 percent of what their teachers say and patients in hospitals have trouble sleeping because they continually feel stressed. Julian Treasure sounds a call to action for designers to pay attention to the “invisible architecture” of sound.

 

What are some of your favorite Ted Talks?

Technicon Acoustics

704.707.0421 | sales@techniconacoustics.com| 4412 Republic Court, Concord, NC 28027

Introduction to Acoustics

Absorption

Have you walked into a racquetball court and heard the echo as the ball strikes the wall? Or have you been in the country with snow on the ground and noticed how quiet it is. The difference in the sound between these to places is due to the degree that sound is absorbed. In the case of the racquetball court, the noise of the ball striking the wall travels to another wall and bounces off of it, travels to another wall and bounces off of it and so on. The echo is caused by the sound continually whizzing past your ear due to reflecting off another wall. In the case of being in a field with snow, your voice either continues to propagate down the field never striking anything, or strikes the snow and disappears. Whether a sound when striking an object reflects back or disappears is due to the objects sound absorption. The racquetball court typically is made of concrete painted walls. Concrete painted walls have very low sound absorption and hence, reflect. Five inches of fluffy snow, however, absorbs the sound when it strikes it.

Some materials allow sound to easily enter it. These materials are called porous. Acoustic porous materials can have a porosity greater than 90%. Porosity is the amount of volume that is just air. Common sound absorption materials are open cell foam and polyester fiber. Sound absorption is an energy conversion process. The kinetic energy of the sound (air) is converted to heat energy when the sound strikes the cells or fibers. Hence, the sound disappears after striking the material due to its conversion into heat.

We know that most sounds contain many different pitches or frequencies. A bass guitar plays low- frequency sounds while a violin plays high-frequency sounds. Low-frequency sounds have long wavelengths and high-frequency sounds have short wavelengths. A wavelength can be visualized when going to a beach. The wavelength is the distance from one wave crest to the next wave crest. In the air, a long wavelength propagates in all directions easily. That is why a single subwoofer is typically needed to fill a listening space due to the fact that subwoofers are not directional in nature. In contrast, a tweeter that emits high-frequency sounds is very directional. Reproduction of high-frequency sounds requires at least two carefully placed tweeters to produce a good stereo image of the sound. Low- frequency sound passes through materials much easier than high-frequency sounds. That’s why one can hear the constant thud of a subwoofer through the wall of the room next door. Because sound passes through materials differently at different frequencies, the sound absorption will typically change with frequency. Besides the sound absorption changing with frequency, it also changes with the thickness of the material. For the same materials, thin sections will not absorb as much low-frequency sound as will thicker pieces. Figure 1 provides absorption curves for the same material at three different thickness. The ordinate (left vertical axis) contains the absorption (alpha). The absorption can go from 0 (no absorption) to 1 (all sound is absorbed). The abscissa (horizontal axis) provides the frequency at which the absorption was measured.

1 – Figure 1. Affect of thickness on absorption

One may be wondering how sound absorption is measured. There are two main methods, one use a special room called a reverberation room and the other uses a special tube called an impedance tube. The reverberation room allows the sound to strike the material from all directions and hence is called random incidence. The impedance tubes have the sound strike the material straight on and are called normal incidence. Table 1 compares the two methods.

2 – Table 1. Comparison between Random Incidence and Normal Incidence Absorption

The Technicon impedance tube is shown below in figure 2:

Figure 2. Impedance Tube for Sound Absorption

The impedance tube consists of a speaker, tube, two microphones and material sample holder. A special sound called white noise is generated in the speaker. The white noise is composed of sound contributions from all frequency bands in the audible range. The sound travels straight down the tube and strikes the material. Some of the sound is absorbed and some are reflected back. The two microphones measure the reflected sound. From the two microphone’s signals, the sound absorption can be calculated.

From figure 1, one sees that one way of increasing the low-frequency absorption is by using a thicker material. Absorption of a non-faced porous material is called resistive. Placing a film on the surface of the material can increase the low-frequency absorption. This type of absorption is called reactive. Figure 3 compares non-faced foam with foam with an aluminized polyester face.

3 – Figure 3. Faced versus non-faced foam for same thickness

Figure 3 shows typical changes when placing a film or facing on the top surface of a porous material. The change in the sound absorption for the faced material is an increase at the lower frequency absorption and a decrease in absorption at the higher frequencies. This is due to the film now acting as a spring-mass resonator for the low-frequency peak. At the higher frequencies, the face causes the sound to reflect. Knowing how different faces can change the absorption of a material, Technicon can design the best sound absorber for our customer’s noise problem.

Sound Transmission Loss

The second technique to reduce noise is sound transmission loss. Sound Transmission Loss is abbreviated as STL. As the name sound transmission loss implies sound is blocked from transmitting through one space to another. For example, a wall in a movie theater separating one theater from the other requires high sound transmission loss to keep from hearing the gunfire, explosions, and crashes from the adjacent theater’s action movie.

There are a variety of ways of producing sound transmission loss. One way is distance. We all know that noisy machines are louder at close distances versus when farther away. When designing a school, for example, distance plays a good common sense noise control solution many times. A poor school design would place a gymnasium or cafeteria next to a library. However, in regards to machinery, distance, as a noise control solution is rarely practical.

Sound is lazy and hence will always take the easiest path to get from point A to point B. The easiest path for sound to travel is a clear unobstructed path. If you can visually see the noisy machine, there is nothing obstructing or reducing the noise from the maximum amount that you could receive. Hence, it is important not to only place something in between you and the noisy machine, but also to make sure that there is no place for that sneaky noise to slip through holes and cracks. A solution for blocking the noise from getting to you would be to place the machine in an enclosure. A well-designed enclosure will always make sound work hard to get to your ears; hence its essential to not have any holes, gaps or cracks. If ventilation is required for combustion intake and exhaust or cooling purposes, a sound silencer or labyrinth is necessary. The labyrinth lined with sound absorptive material forces the sound to strike the sound absorptive material hence causing the sound to be reduced significantly by the time it exists.

Now that the enclosure is pretty well sealed, sound can still reach you by transmitting through the enclosure walls. This is called airborne sound transmission. There are ways of increasing this sound transmission loss. The first is mass. Mass can be increased by using a thicker wall of the same material or use a more dense material. There is a relationship between sound transmission loss and weight of the barrier and this is called the mass law. The mass law states that for every doubling of the weight of the material, one can expect a 6 dB increase in the transmission loss. In addition to the mass having an effect on the transmission loss, the frequency of the sound also has a similar effect. A doubling of the frequency will create a 6-dB increase in the transmission loss. Figure 4 shows the effect of mass and frequency on sound transmission loss.

4 – Figure 4. Mass and Frequency dependence on Transmission Loss

One sees that the cost and weight of the wall must double for each 6 dB incremental improvement in transmission loss. If there are two walls and they are separated by a significant distance, each wall transmission loss is additive. This additive effect is shown in figure 5.

5 – Figure 5. Comparison between double and single wall for same total weight.

One can see from figure 5 that by adding a second wall and large air gap between the walls, the transmission loss can be dramatically increased. Double wall construction is encountered in many everyday systems. For example, in homes, drywall, stud construction is made of two sheets of drywall separated by the studs.

In the real world, the air gap between walls will be relatively small. In machinery enclosures, the gap may range from 1/4″ to 2″. The greater the gap, the more the walls behave as two separate walls instead of a single wall comprising of both walls total weight. In real-world double wall systems, a double wall resonance in the airspace occurs which reduces the transmission loss. To reduce the detrimental effect of the double wall resonance, a foam or fiber is placed in the air gap between walls. Technicon offers a variety of barrier composites. Barrier composites create a double wall system when attached to the interior wall of a machinery enclosure.

Vibration Damping

Many time’s large panels vibrate. The cause of vibration may be an engine, generator, compressor, road irregularities in vehicles or a boat hull slapping against the waves. When this occurs, the panel vibrates as a large speaker cone creating noise. This type of noise is called structural borne noise. The greater the panels move, the more air is displaced, the louder the sound. The vibration creates resonance in the panel causing it to move. Resonance is a natural phenomenon that can cause a mechanical structure to vibrate violently if the panel is excited at the same frequency that a resonance occurs. To keep a panel from resonating violently, the panel must be damped. Steel or fiberglass panels by themselves are stiff and elastic, causing them to vibrate a long time when struck. Hence, steel and fiberglass have very little damping. Hence, to damp the panels to reduce resonant vibrations, damping must be applied to the surface of the panels. Damping materials can be applied as a trawled on a compound or as sheets with an adhesive backing. The key feature of a damping material is that they are viscoelastic. Viscoelastic materials require energy to be extended and compressed. This is exactly where we want the vibration energy from the panels to go, into the viscoelastic materials and then dissipated as heat.

The amount of damping necessary to effectively reduce the panel vibrations is dependent on the panel thickness and material type. If one overdamps the panel, this adds extra cost and weight, hence, there is an optimal amount of damping for a given panel material and thickness. There are test standards to measure the damping loss factor of the damping material. The test standard performed at Technicon is ASTM E756. A picture of the test fixture for measuring the damping loss factor is given in figure 6.

Figure 6. Damping Test Rig with Sample

 

The damping test rig consists of a bar made from the panel material with the damping material bonded to it. Like the impedance tube, a white noise signal is fed to a vibration exciter at the top of the bar. This causes the bar to resonate. At the bottom of the bar, a vibration pickup measures the bar’s resonance. The transfer function is defined as the output vibration response of the bar divided by the input vibration excitation is calculated. This is shown in figure 7.

6 – Figure 7. Transfer Function of Damping Bar

The peaks in figure 7 are excited resonance in the bar. The broader the resonance peaks, the greater the damping. The composite damping loss factor is calculated by the formula:

Composite Loss Factor = [fh(-3 dB)- fl(-3 dB)]/fr

Where:

fr = Frequency at resonant peak

fh(-3 dB) = Higher Frequency at -3 dB below resonant peak

fl(-3 dB) = Low Frequency at -3 dB below resonant peak.

7 – Acoustics Lab for Reverberation Testing

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