The Asheville Humane Society in Asheville, N.C., had a serious animal noise problem at its facility and with the help of Acoustiblok, a NASA “Spinoff” listed company, the problem was solved with Acoustiblok’s patented AcoustiFence. This cutting-edge 1/8-inch-thin outdoor sound barrier is engineered to reduce noise, such as loud dog barking, as well as many other types of noise encountered daily at an animal shelter.
In fact, the United States Patent Office awarded Acoustiblok a 20-year patent on AcoustiFence and the material was just tested at Hurricane Engineering/Test Lab to withstand up to a 200-mph wind load (that’s over a category 5-plus hurricane!).
Eco-friendly, unique AcoustiFence is a heavy, limp, mineral filled (barium/lead free) viscoelastic acoustical material that is placed between the noise source and the noise receiver. Because AcoustiFence is so thin, it is easy to position it closer to the noise source such as in or outside kennels and other animal chain-link fence enclosures. The closer a barrier is to the noise source the more restricting (reducing more) it becomes to the initial sound waves (noise).
AcoustiFence has a unique characteristic that sets it apart from other sound barriers when dealing with a range of acoustic frequencies from numerous sources; the heavy limp AcoustiFence material actually vibrates from sound waves. In essence, it’s transforming these sound waves into mechanical movement creating inaudible internal friction energy.
The Project
When the Asheville adoption center was built more than 10 years ago, it met and exceeded all the guidelines for an animal sheltering facility. However, over time, an unforeseen design flaw came to their attention; unfortunately, the cat and dog areas, while separate, were very close together. There was no way for cats to escape the noise of barking dogs and no way for dogs to escape the noise of other barking dogs (sound meter readings showed 100-120dB when the dogs were aroused and 75-80dB during normal day activities). This greatly increased the stress level of the animals who were already trying to adapt to a new environment. Excessive noise can cause more undue stress and delay an animal’s readiness for a permanent home.
Keeping in line with the organization’s mission to maintain a state-of-the-art facility and provide every animal in their care with a life worth living, shelter representatives contacted Acoustiblok to resolve the noise issues. State standards require that certain materials be used in animal facilities. Asheville Humane Society chose to work with Acoustiblok because of the company’s reputation in the industry, and because AcoustiFence, sound deadening material, exceeded the state regulations. They were very confident that installing the outdoor acoustical material would greatly minimize the negative effects of the continuous dog barking and other harmful noises affecting the animals, staff and visitors at the center as AcoustiFence is engineered to reduce a wide range of acoustic frequencies, by both sound blocking (STC30) and sound absorbing (NRC.78—at very low frequencies).
AcoustiFence easily can be suspended from a chain-link fence up to a height of 20-feet by simply overlapping the sections. And because it is easily attached to a chain-link fence, it eliminates the need for expensive permitting or structural requirements.
Once installed, the cats in the temporary care area would be able to play, nap, and do cat things without the constant stressor of barking dogs. Similarly, the dogs in their care would be able to enjoy playtime outside without the often-disruptive stimulus from the sight and sound of other unfamiliar dogs.
Acoustics in Animal Shelters
Sound plays a very significant role in an animal’s day-to-day life. This is especially true for displaced animals who may be suffering from anxiety disorders. Most pet owners are unaware of the strong impact that high noise levels have on animals in the home environment, and this is also true for veterinarians and volunteers working with displaced animals. Prolonged high noise levels can cause anxiety which can hinder an animal’s healing process and cause lifelong phobias if not properly treated.
Sound is a type of mechanical radiant energy transmitted by longitudinal pressure waves. Its frequency, or pitch, is measured in hertz (Hz). One Hz is defined as one cycle per second. Hearing ranges vary from animal to animal; humans are able to hear frequencies from approximately 64–23,000 Hz, dogs between 67–45,000 Hz and cats from 45-64,000 Hz. Both dogs and cats are able to hear sounds much farther away than humans can.
The intensity or power level of a sound is measured in decibels (dB). Hearing damage can occur instantaneously at 100dB or higher and permanent damage can occur with prolonged exposure to levels above 85dB. A single dog can reach a very loud 80-90 decibels and when you have a group of dogs such as those in a kennel or shelter, the typical noise level can reach and maintain an alarming and deafening 120 decibels or higher.
To put it in perspective, normal human speech is around 60dB; an automobile 80dB and a jackhammer 90dB. Louder than 85dB, damage to the hearing is possible after two hours.
Bioacoustics, the study of how sound affects living organisms, is especially interested in the ways in which animals communicate as well as the positive and negative effects of sound in their habitat or surroundings. Psychoacoustics studies the physiological responses of sound on humans. This includes how people listen, and the psychological and physiological responses to music and sound on the nervous system. Current research suggests these psychoacoustic concepts also apply to animals.
An important neurologic concept in sound attentiveness is the orienting response; this occurs when the nervous system becomes aware of a stimulus. With sound, whether the individual is consciously aware of it or not the brain engages and reacts to it via the nervous system. When it’s a low-level stimulus (low noise levels), the nervous system can return back to a calm state fairly quickly. When it’s a high-level stimulus (high noise levels) the fight or flight response is triggered.
Dogs, cats and other animals in kennels or shelters are exposed to high levels of noise primarily due to uninterrupted dog barking and because the construction materials typically used (tile and concrete) in building them amplify acoustic noise levels. Unfortunately, this can result in the noise-induced hearing loss (cochlear damage) in both animals and humans when exposed to excessive amounts for extended periods of time (Dogs in animal shelters are typically exposed to sounds that are in the 100dB or higher range throughout the day—this is 1000 times higher than a dog can actually endure without experiencing pain and hearing damage).
Loud noises can also trigger strong emotional reactions such as fear and anxiety in animals, depending on the type of noise and its duration. This can provoke concerning physical displays of shaking, panting or seeking comfort to more serious aberrant behaviors such as defecation, urination, self-mutilation, and vomiting.
In addition, current research indicates some dog breeds are more fearful of loud noises than others and female dogs are 30-percent more likely to be more fearful of noises than are male dogs. Neutered dogs are a surprising 72-percent more likely to be fearful of noises when compared to their counter parts.
These issues make it vitally important to reduce noise levels inside facilities as well as outside areas where animals spend time.
The AcoustiFence Installation
First, the green shade reinforced AcoustiFence was installed between the dog exercise yards and the screened-in cat porch to reduce the noise between the dog and cat areas. The second area treated with the sound-deadening material was the fence between the exterior facing dog runs and the dog walking courtyard. Treating this area enabled the dogs to relax while out on their walks or behavior assessments and provide a calm environment for fearful dogs or those recovering from illness or injuries. The fence around the HVAC units was also treated with AcoustiFence to reduce the added high-volume noise of the multiple units housed on the property.
Jim Fulton, chief of Constituent Services, says: “We can’t thank the folks at Acoustiblok enough. The Acoustiblok staff were very helpful throughout the whole process. And we are so happy with the results! It has made a huge difference on the physical and mental well-being of the animals, the staff working here and our visitors. Their high-quality sound blocking AcoustiFence material was easy for us to install and allowed us to eliminate one more roadblock as we strive to improve the shelter experience and mental health of the animals and the people who pass through here. In turn, this will speed up the adoption process for our feline and canine guests dramatically, allowing us to save even more lives each year!”
2 Comments
Thank you for your question Steve; unfortunately, the Asheville Humane Society was not able get any sound meter readings for us at the time and were most concerned about the results (this is true for many of our customers). In addition, after 20 years in this business, we’ve found that acoustic readings in and of themselves cannot tell the whole story; loudness and what’s considered “noise” is very much in the “ear of the beholder”. This of course, can vary from person to person, but more importantly varies from species to species. The shelter was not only concerned about the staff and visitors, but also about the welfare of the animals there (they also wanted a privacy barrier). After the AcoustiFence installation, they informed us that it made a significant positive difference on the physical and mental well-being of the animals, as well as the staff and the visitors. We do have technical information available on AcoustiFence, if interested please contact Jim Ashley at [email protected]
Why is there no numerical data provided on decibel reduction. It realize that sound travels in waves and that more noise will be present further from the barrier, but the article could provide at least some data up against the barrier.