What is PET?

Polyethylene terephthalate, or PET, is a thermoplastic polymer resin comprised of recycled transparent plastics. PET is frequently referred to as polyester in textile applications but retains its acronym PET regarding packaging, bottling, etc.

Polyester was first patented in the 1940s by Dupont chemists in Delaware, U.S.A, as a new textile fiber. It wasn’t until the 1970s that new technology made it possible to mold PET into bottles. Today, it is the number one recycled plastic worldwide.

PET is highly flexible in its natural state and therefore easily moldable for its end use depending upon how it is processed. Its applications as the number one recycled plastic range from food packaging and bottling to fabrics to thermoforming in manufacturing and automotive insulation.

The textile industry is a significant end-user of PET, making up about 60% of overall PET consumption.

What is Polyester Felt?

Polyester felt is made of recycled PET plastics, mostly water bottles or other single-use products. The recycled material is compressed and melted down until left with plastic flakes. The plastic bits are then remelted and extruded as fiber. This fiber is then used to produce rolls or sheets of PET textile material, similar in any felting process. It can contain anywhere from 0% to 100% recycled content. Not only is it sustainable, but it is fast becoming the premium choice for sound dampening performance in lieu of other traditional materials, like fiberglass.

Polyester felt’s lightweight durable nature (combined with an additional lower melting point ) create the ideal properties for acoustic felt panel design. Its capability to be easily cut, variety of color options, and limitless forms are making polyester acoustic panels part of the visual landscape in modern interior design.

Restaurants, bars, cafes, hotels; we leave the comfort of our homes to indulge in these spaces.

COVID-19 restrictions have eased and the long-desired opportunity to frequent our forgotten social lives is now present. Properly designed noise control measures in your public spaces can make a difference between a returning customer and a bad Yelp review in these post pandemic times.

Sound: A Health Risk

We cannot escape noise.  Our daily lives are inundated with a variety of sounds from the landscapers outside our homes to the swirling conversations surrounding us at the bar.

The most serious potential risks to our health are:

• hearing loss
• hearing impairment
• tinnitus

But the most pervasive effects trigger issues with our physiological health.

Fact: Sound levels above 85 dB are considered harmful. Exposure to sound levels at or above 120 dB can cause immediate damage.

Sound disrupts our sleep, concentration, heightens our stressors by releasing cortisol, elevates blood pressure and heart rate…

And, to put it simply, too much sound is annoying. We don’t see noise or feel it, so we write off issues as non-noise induced. But for the average guest, noisy spaces make for uncomfortable environments.

Why So Noisy?

The number one complaint when dining out is poor service. The second is noise.

So when did the hospitality industry become so noisy? And why?

The trending upward levels of noise may have started in the mid-1990s with well known chef Mario Batali when he began playing the music in the kitchen and dining area. Now it has become commonplace to amp up the volume to create a “buzz” that draws people in.

It has also become a tactic for quicker turnaround. Research has shown that restaurant and bar owners use excessive levels of noise because it pushes patrons to eat faster thereby leaving sooner.

All five of our senses influence our perceived reality of not only places, but the food and drinks we consume. But further scientific research has shown evidence that noise interferes with our sense of taste. Because noise is a distractive nuisance, it becomes easy to mess with the senses.

Other purposeful choices in décor amplify noise. Modern design trends are the greatest conductors of sound. Gone are the days of plush booths and tablecloths; elements of style that helped dampen noisy spaces. Substituted with glass tables and bare floors, sound now bounces around freely with little absorption opportunities.

Where to Look for Acoustic Problems

To understand sound, it is good to know the basics of how sound travels.

Sound is vibrational energy. There is direct sound which travels directly from the source to the receiving end (for example, you and your partner talking over breakfast in your apartment). And then there is reflected sound. Reflected sound is direct sound bouncing off walls, floors and other mediums. The reflected sound is what gives us reverberations or echo. And why sound becomes exasperated in most spaces.

Think of a disco ball except with loud music, kitchen sounds, employees working, and the rolling conversations all overlap and bounce off one another making for, “Say that again” and “I can’t hear you” staple quotes of the night.

Sound treatment can be expensive. Hiring acoustic engineers and sound consultants can drive up the price. And altering your already designed interior can create issues for an already established institution.

There are simple ways to addressing noise issues without mind blowing renovations. First, taking inventory of intentional noise practices (as we mentioned, loud music) coupled with the décor of your space will help you pinpoint where sound is amplified.

Keep in mind the materials in your space (hard materials like steel or glass are non-absorbing) and the landscape of your interior. A cheap alternative to testing for room acoustics is a simple clap test. In your space, clap your hands together and wait to hear for the initial “slap” followed by its echo. The longer the sound continues, the more reverberation time your room holds. It’s an easy way to hear for where your acoustical problems lie.

Balancing Noise Levels with Acoustic Treatment

Thankfully, acousticissues in your space are not a unique problem. And most acoustic insulation solutions do not have to take away from the defined aesthetic of your brand.

The addition of acoustic panels improves sound quality by reducing the amount of reflected sound. Materials like PET (recycled polyester) absorb sound waves, dampening the sound by transferring the vibrational energy into kinetic energy, or heat. And they come in a variety of forms. Placing your acoustic panels accordingly (and relative to your space and its dimensions), you can effectively mitigate noise.

What Types of Acoustic Panels are Best for You?

Sound is the main issue. Turning off the music won’t change sound traveling. To find the right acoustic treatment, you need to take these things in to consideration:

• Dimensions of your space (high ceilings, etc.)
• Furniture materials, flooring, windows, doors
• Noise absorbing material and “dead” space

Keep in mind the tone of your space. Acoustic panels do not have to dull the vibe; with so many options and designs, you can enhance without compromise.

Here are some acoustic solutions that can fit in to your space.

Acoustic Panels and Art

Acoustic panels can be any size and shape, placed in a variety of configurations at designated reflections points. In this scenario, less can be more, enhancing walls with modern visuals.

Acoustic panels can also double as artwork. Stock photos or custom images can be printed onto any size panel to give you a piece of artwork that works as your sound dampening tool. And in our post-COVID world, you can utilize acoustic panels as custom dividers (movable or fixed) for designated areas that will buffer sound and maintain safety regulations. They can also act like booths without the bulky nature.

Ceiling Baffles and Clouds

To better your bar and restaurant guests’ experience, hanging acoustic solutions can mitigate noise in a non-conspicuous manner. Or conspicuous: they are perfect examples of how to create artistic focal points in your space. Depending on shape and size, they are effective at tuning out unwanted noise in greater ranges of angles.

Plus, they can double as lighting fixtures, creating a two for one in your space’s décor.

Absorbent Furniture

One product, multiple functions. Sound absorbing furniture works well for physical comfort and sound buffering. In modern and sleek establishments, complimenting stark lines with plush furniture in lobby and rest areas soften trending contemporary styles and invite your patron so stay.

You Don’t Need to Reinvent the Wheel for Sound Management

Rendering your space acoustically “healthy” for patrons (and employees) can be easy without re-designing.

At Oppeo, we manufacture our EcoPanel Acoustic panel line to meet any acoustical need. Our panels are 100% polyester, free of any fiberglass or VOC, and customizable for all specialized products. From rolled good to hanging baffles, our partially recycled acoustic panels create top quality finished products.

To understand the challenges that arise on the quality front, you first have to understand how polyester acoustic panels are made.

1. Define the desired outcome

The process to create a finished acoustical panel starts with determining what characteristics we want the finished panel to have. We can affect acoustical curves (NRC), stiffness, surface texture, or color by changing the fiber material or size, product density or thickness, or manufacturing processing of our finished panels. Each variable lets us dial in the ideal finished characteristics. Our standard Eco panels are comprised of recycled polyester fiber and special lower melting point polyester fiber.

2. Manufacture the needle punch felt

Next, we start the manufacturing process. Every polyester acoustic panel starts out life as a nonwoven, needle punch felt. This felt is similar to the felt kids make craft projects out of, but much thicker and denser!

We begin by taking raw fiber and turning it into a “web”. We then build density and surface characteristics by adding batts and needling the material together. The repeated needling that the felt receives is one of the keys to creating a stiff panel while maintaining a super smooth-surfaced panel. From this process, we create a “master roll” of felt.

3. Heat-setting

The felt moves to the heat-setting machinery following the creation of the master roll. This could be a mold for 3d shaped panels or some form of flat pressing system. This process changes the material from a roll of flexible felt to a stiff polyester acoustic panel.

When heat hits the polyester fibers, they melt and flow like a liquid thermo-plastic. Fibers like these are specially designed to have a low melt point. As this material cools, it turns back into plastic but is now spread throughout the felt, attached to all the fiber around it, and (with the assistance of the needling) creates the stiffness of the finished acoustic panel.

The heat-setting process is one of the most difficult to perfect. This is because the material will shrink three-dimensionally while being heated. And any imperfections in needling will create very obvious surface defects.

4. Cutting

The final manufacturing step is to cut the panels to their final dimensions or shape. Most architects and interior designers need tolerances of +/- 1/8th of an inch. Some elaborate designs require tighter than +/-1/16th of an inch. This would normally favor a die-cutting process but in many cases, the variety of shapes and rectangular dimensions needed would make this cost-prohibitive. Only with extremely precise cutting tools such as CNC machinery using oscillating blades, lasers, or waterjet cutting can near-perfect acoustical panels be cut every time.

What quality attributes should you look for when assessing polyester acoustic panels?

There are several factors to consider when determining whether a polyester acoustic panel is of top quality.

Uniformity

Is the first panel just like all the others and, also as important, is each individual polyester acoustic panel consistent within itself?

One of the key giveaways of an inconsistent process is that one panel does not look like the next. When dealing with large-scale projects, even minor consistency problems can stand out when looking from panel to panel or from one section of a panel to another. Unfortunately, due to the nature of the panel manufacturing process, it is impossible for panels to be exactly identical, but the closer they are, the better.

Blending

The distribution of colors in a panel is one of the first things to stand out. Many panels have a “heathered” look to them. This comes from blending two or more colors of fiber together. Do you see clumps color? Or is everything evenly spread out?

Thickness

Another one of the most noticeable attributes comes when comparing the thickness of different panels. When placing panels next to each other on a wall or in a line of desk dividers, check to see if the panels are of different thicknesses.

The thickness of each acoustic panel is one of the major drivers of its acoustical absorption capability. Thicker is better!

Stiffness

Many applications for acoustic panels, such as desk dividers, require very stiff panels. Make sure to check if the panels stiff enough for your use. Is each panel consistently stiff? This could be from one corner to another or from one surface side to another.

Many manufacturers struggle with getting enough heat all the way through the panels to fully activate the low-melt fiber. This is especially true on thicker panels. Often, an inferior panel will have a softer center and two harder surface faces when you look at the panel from the side. When this happens, the panels tend to not hold mounting bolts or hardware as well and also tend to collapse and bend easily when held from only one side. This usually destroys the panel by creating unwanted wrinkles on the surface.

Acoustic Certifications (ASTM C423)

Polyester acoustic panels have many uses, but as the name implies, “acoustic” tends to be the key attribute for many applications. All panels should have an NRC value, and most “standard” specifications will.

Where this gets tricky is when comparing panels from different vendors that look the same but have vastly different ASTM C423 results. Logic says that the higher number is better, right? Well, not quite…

There are different variations of the ASTM C423 test. These range from “A” mount where the acoustic panel is placed directly against a cement floor (and will have a lower NRC number) to “E Mount” where the panel is suspended several inches in the air (and the NRC number will be higher). It isn’t wrong for a vendor to use “E” mount test data, but make sure you compare apples to apples when comparing!

As a secondary note for ASTM C423 testing that produces an NRC value, keep in mind that NRC is an average of performance at different frequencies. If you have specific acoustical profiles or sound frequencies that you need to target, then make sure you look at the charts to compare performance at your specific frequency.

The acoustical curve of . 45 (9mm thick) acoustical panel using ASTM 423 A-mount. Note the different absorption coefficients at different frequencies. NRC: 0.30

Flame and Smoke Certifications (ASTM E84)

The ASTM E84 certification uses a combination of a flame spread and smoke generation test. It is one of the most important certifications for applications that are considered “building materials”. Depending on your application, you may not require this certification, but most suppliers will have their acoustic panels tested to this specification.

There are several results possible all resulting from the flame spread portion of the test. The generally accepted standard is “Class A” and, if your application requires this test then be sure to look for this.

One word of caution here, not all ASTM E84 tests or testing labs are equal. Many of our customers are wary of using unknown foreign laboratory results for good reason. We have heard some horror stories about vendor-provided laboratory results looking good but when independently tested their panels fail miserably.

Due to the moral values and legal penalties involved in failing this test, most of our customers will conduct their own testing using a US certified lab. We recommend that you do the same if you do not personally know the lab that conducted the testing.

What to look for in a vendor

Now that we have reviewed the critical parts of a quality panel, it is easier to identify what to look for (and what we strive to be!) in a vendor as well. For many customers, being able to provide a consistent, high-quality panel is paramount and all-encompassing. Other normal vendor characteristics to inquire about are minimum order quantities, lead times, and, of course, price. However, there are a few other factors to consider that not every PET acoustic panel vendor can provide.

First is the ability to customize. The market is becoming flooded with 9mm thick panels that look, feel, and perform pretty similarly. But your company might require a distinct acoustical performance curve, custom color options, or different thicknesses. Finding a supplier who can work with you to provide the exact product you need isn’t always needed, but be sure to review your requirements and make sure the company you are working with can handle them.

Another often overlooked aspect of vendor capability is someone you can build a relationship with. Maybe you are in a bind and need an order shipped early. Or you are stuck with a whole truckload of panels after a customer backed out of a deal. Is your vendor willing to take them back no questions asked? Finding a company that you can work with is often worth paying a bit more when they save you headaches down the road!