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Are sound absorbers safe for our health?

Yevhen

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I've always wondered if these absorbers we all use are safe for our health. Has anyone tried to figure this out? All of them have an open structure, which means tens or hundreds of square meters of the actual surface to evaporate during aging.

What type of absorbers are relatively safe? And not fire hazardous :)
 

MRC01

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Absorbers often contain fiberglass, which can shed stray fibers that damage skin, eyes, lungs. I used gloves and a mask when handling the fiberglass and constructing my tube traps. But the fiberglass is typically inside the device wrapped with cloth or similar coverings that would trap most of any stray fibers that come loose. As least in my case it is.
 

BinkieHuckerback

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...seriously? Do you drive or cross the road on foot? How long are you expecting to live?
 

MRC01

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Remember, fiberglass is in the walls of most houses & apartments too... it's a common material used ubiquitously. Potential negative impacts from fiberglass or any other potentially harmful substance depend on exposure and concentration. In many cases the only difference between medicine and poison is dosage.
 

Yasuo

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Remember, fiberglass is in the walls of most houses & apartments too... it's a common material used ubiquitously. Potential negative impacts from fiberglass or any other potentially harmful substance depend on exposure and concentration. In many cases the only difference between medicine and poison is dosage.
This is nonsense, you have some pretty solid separation between the fiberglass (drywall, plywood etc) and there's no air movement bothering that fiberglass.
 
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Yevhen

Yevhen

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Yes, I think the main difference here is that you need to keep the structure open for the airflow
 
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Yevhen

Yevhen

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I've built DIY panels from the 5cm recycled paper absorber sheets but those seem to be much less effective compared to my old melamine Hofa panels
 

MRC01

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This is nonsense, you have some pretty solid separation between the fiberglass (drywall, plywood etc) and there's no air movement bothering that fiberglass.
The separation is not as solid as you might think. In crawl spaces and attics the fiberglass is often exposed. And you can get air movement through these spaces, especially on windy days. My point is that fiberglass is all around us: houses, sports equipment, cars, etc. Just because something has fiberglass in it doesn't automatically make it hazardous. It may or not be, depending on the situation.

I used a gloves & mask when handling raw fiberglass for my tube traps, but I don't feel that is necessary when handling them now, or when being in the room, as they are fully covered with 2 layers of fabric. Do enough fibers escape to cause a health hazard? I doubt it, they've been there for 10 years and I haven't noticed any dust or fibers when handling them or when cleaning the room. Nobody has been coughing or sneezing. Since they're wrapped, I don't worry about it. Just my experience, anecdotes are not evidence, etc.

That said, I would not have an acoustic treatment with exposed fiberglass in my room. Even if the exposed fiberglass were inside, I'd want it covered to prevent migration of flakes/dust.

PS: let's not restrict this solely to acoustic treatments. I've seen speakers with fiberglass inside that are ported. Due to the driver motion you can feel the air pumping in and out of the port...
 

Glen20

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Great question Yevhen

Simple scientific answer is it depends on exposure ie dose and time. We will have higher exposure due to proximity to products airflow, suspending dust in air and the time spent in our treated rooms
From info in links below
Answer No.

  • If it contains fibreglass as either the absorption material or binding agent or as part composition of rock wool.
  • It is foam. Some form of plastic. New or recycled It will contain fire retardant as far as I know
Answer Probably no ( maybe)

  • Mineral wool /rock wool / basalt wool /recycled slag wool if dust expelled during use (see wiki link below)
Answer Probably yes ( guess)( as long as no mold grows)

  • wool, hemp, flax,wood,cork
Due to the mineral wool non-degradability and potential health risks, substitute materials are being developed: hemp , flax wool, wood and cork insulations are the most prominent. Bioavailability and health profile are the main advantages of those materials. Their drawbacks when compared to mineral wool are their substantially lower mold resistance, higher combustibility and slightly higher thermal conductivity (hemp insulation: 0.040 Wm-1k-1, mineral wool insulation: 0.030-0.045 Wm-1k-1).(from wiki link)

https://www.theguardian.com/us-news...s-flame-retardants-firefighters-safety-cancer

https://www.theguardian.com/us-news/2019/may/24/flame-retardants-everyday-products-toxics-guide

https://www.niehs.nih.gov/health/topics/agents/flame_retardants/index.cfm

https://en.m.wikipedia.org/wiki/Mineral_wool

Caution Knauf earthwool actually contains fibre glass
 
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Yevhen

Yevhen

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Wow, great
Great question Yevhen

Simple scientific answer is it depends on exposure ie dose and time. We will have higher exposure due to proximity to products airflow, suspending dust in air and the time spent in our treated rooms
From info in links below
Answer No.

  • If it contains fibreglass as either the absorption material or binding agent or as part composition of rock wool.
  • It is foam. Some form of plastic. New or recycled It will contain fire retardant as far as I know
Answer Probably no ( maybe)

  • Mineral wool /rock wool / basalt wool /recycled slag wool if dust expelled during use (see wiki link below)
Answer Probably yes ( guess)( as long as no mold grows)

  • wool, hemp, flax,wood,cork
Due to the mineral wool non-degradability and potential health risks, substitute materials are being developed: hemp , flax wool, wood and cork insulations are the most prominent. Bioavailability and health profile are the main advantages of those materials. Their drawbacks when compared to mineral wool are their substantially lower mold resistance, higher combustibility and slightly higher thermal conductivity (hemp insulation: 0.040 Wm-1k-1, mineral wool insulation: 0.030-0.045 Wm-1k-1).(from wiki link)

https://www.theguardian.com/us-news...s-flame-retardants-firefighters-safety-cancer

https://www.theguardian.com/us-news/2019/may/24/flame-retardants-everyday-products-toxics-guide

https://www.niehs.nih.gov/health/topics/agents/flame_retardants/index.cfm

https://en.m.wikipedia.org/wiki/Mineral_wool

Caution Knauf earthwool actually contains fibre glass
Great overview, really thanks! I was always more into the last group:
  • wool, hemp, flax,wood,cork
Maybe you also know some panel manufacturers, not too expensive? Sometimes I think it might be cheaper to buy secondhand books and let them absorb. Of course it's much less effective. Do you guys have any ideas? Thick carpet on the wall?
 

MRC01

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Carpet, curtains & similar materials can have an audible impact on mid-high frequencies, which can be helpful. Yet one of the most important things with room treatment is to reduce modes which are in the low frequencies. Due to the long wavelengths of these sounds, this requires physically large treatments, or treatments having tuned resonances (weighted/tensioned membranes etc.).
 

bravomail

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Absorbers often contain fiberglass, which can shed stray fibers that damage skin, eyes, lungs. I used gloves and a mask when handling the fiberglass and constructing my tube traps. But the fiberglass is typically inside the device wrapped with cloth or similar coverings that would trap most of any stray fibers that come loose. As least in my case it is.
yes, many absorbers are cheaply made using some dangerous materials. Use wall and floor carpets - they worked well for ages! :)
 

Inner Space

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Sometimes I think it might be cheaper to buy secondhand books and let them absorb. Of course it's much less effective. Do you guys have any ideas?
Books are a pretty good idea, overall. They're lumps of wood fiber, of random size, depth and density. If you don't line them up neatly, collectively their front faces act a bit like a skyline diffusor.

Another idea - I saw a situation where a guy (who had similar concerns) made some deep panels packed with ordinary fluffy pink fiberglass - but never unpacked from the vacuum seal they came in. In other words, he just crushed the round bales into the space. The effective increase in density made the fluffy work better, and the original plastic wrap was defense against leakage. Anything packed for interstate shipment into, e.g., California is going to be safe enough.
 

youngho

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I've always wondered if these absorbers we all use are safe for our health. Has anyone tried to figure this out? All of them have an open structure, which means tens or hundreds of square meters of the actual surface to evaporate during aging.

What type of absorbers are relatively safe? And not fire hazardous :)
Since you're in Europe, you could certainly consider Basotect (https://plastics-rubber.basf.com/global/en/performance_polymers/products/basotect.html) and Caruso Iso-Bond (https://www.don-audio.com/acoustic-absorbers). There are also wood fibre-based products, as well.
 

MRC01

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... Another idea - I saw a situation where a guy (who had similar concerns) made some deep panels packed with ordinary fluffy pink fiberglass - but never unpacked from the vacuum seal they came in. In other words, he just crushed the round bales into the space. The effective increase in density made the fluffy work better, and the original plastic wrap was defense against leakage. Anything packed for interstate shipment into, e.g., California is going to be safe enough.
If the fiberglass is sealed inside plastic wrap, doesn't that prevent it from absorbing acoustic energy as the sound cannot pass through it?
I thought that in order to function properly, they need to be wrapped in something that is relatively transparent to air movement, yet retains any fibers that the fiberglass might shed. Typical fabric type coverings.
 
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Yevhen

Yevhen

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I fully agree, confirmed by experiment. Tried to wrap the foam with polyethylene, it doesn't work. The foam or glass needs to have an open structure and the air should be able to move through it in and out
 
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Yevhen

Yevhen

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