[JonnyFive]

I have a dedicated listening space that is 15' w x 8.5' h x 42' l, and there's a ton of slap echo.  I ordered two boxes of 4' x '8 Owens Corning 703 Black Select Sound rigid fiberglass boards (8 pieces total).  I'm planning to initially treat the front of the room, and later, all the primary reflection points.

But now I've got myself worried about having fiberglass board just sitting there exposed (even if under a Guilford of Maine fabric, the particles can/will still be released).

Am I over-thinking this from a health standpoint?

I thought Rockwool would be an alternative, but  it emits many particles as well.  My thinking is the rigid fiberglass board maybe less likely to emit particles due to the bonding.

Jon 

[S Clark]

You can stabilize the surfaces with something like clear lacquer.  I've even heard of using hair spray

[JonnyFive]

I am planning on making 4" traps out of the 2" panels.  The Select Sound has a black finished face, one unfinished face, and unfinished sides.  I can do some fiberglass resin on unfinished-to-unfinished to make the 4" thickness. Then, fiberglass resin around the outside edges to seal it.  That should significantly help any particles, I think.

[S Clark]

You really don't need to seal anything.  Actually, anything that would actually seal or restrict air flow in any real way would be counterproductive.  Just make sure that loose particles are stabilized, and that there is a cloth covering.  "\
"Am I over-thinking this from a health standpoint?"  Yes. 

[JonnyFive]

Do you think sealing just the edges would negatively impact the acoustical properties?  Not much sound enters from the sides. 

[S Clark]

Do you think sealing just the edges would negatively impact the acoustical properties?  Not much sound enters from the sides.

No, a small sealed area is no big deal, but why bother? Just keep the fibers from getting into the room. 

[thunderbrick]

"Am I over-thinking this from a health standpoint?"  Yes.

+1!  Main thing is, don't tear them up and turn the fibers loose.

[Big Red Machine]

If you're not disturbing by rubbing them or cutting them then the fibers are happy staying where they are.

[brj]

Since you've already purchased your product, I'd consider this simply food for thought relative to future projects...

My understanding is that the biopersistance of mineral wool is lower than that of fiberglass, but both are "synthetic vitreous fibers" (SVFs) and less of a concern than once thought.  Basically, asbestos fibers are the ones that don't break down easily in the lungs and thus hang around to cause problems.  That said, the safety details will come down to the specific product you're considering, as it's dependent on fiber size, raw material, etc..  There is a "note q" on some European standard that I can't quite recall that is designed to draw the line for what SVFs are safe relative to human inhalation.  Using some of the terms mentioned above should provide plenty of Google hits if you feel so inclined.

Note that mineral wool is naturally hydrophobic, and thus more or less immune to humidity, which in turn means that it  won't support mold growth, etc..  When last I looked (not recently), fiberglass had to be treated to provide moisture resistance.  Likely not an issue in your application, but worth noting for other applications.

Mineral wool can also withstand much higher temperatures than fiberglass.  This isn't a factor in most acoustic treatment situations, but it mattered to me when I wanted to damp the sound of the blower motor and fan on my gas fireplace, as the insulation was in direct contact with the firebox.  (It could also matter if you wanted to insulate around can lights in a ceiling or similar.)  I went with one of the semi-rigid Roxul "Safe" series of products.  (They have a "Safe'n'Sound" product that specifically advertises acoustic benefits, but I believe that all of the "Safe" products are similar, except for density.)

Hope that helps!

[mcgsxr]

If you encase it in fabric you are good.

I used rigid Roxul as it was available.  I covered it front and back with cloth. 

[JonnyFive]

The plan is to encase it in acoustically transparent cloth.  Thanks for putting my mind at ease, everyone.

[S Clark]

I'm actually in the process of building a couple more bass traps myself. 
Step 1:  cut four 18" circles of plywood
Step 2: cut  8 pieces of 1"x2"x4'
Step 3:  tack the strips to the plywood ends
Step 4: tack wire (any variation of chicken wire/hardware cloth) nearly around the frame, leaving opening to stuff fiberglass
step 5:  Fill with fiberglass
Step 6: finish tacking
Step 7:  put the whole thing in a large coffee sack, and staple to close.  Or use that left over Jackson Pollack that's in your closet for a covering... just as long as the canvas breathes.
Done.

I cut everything and built one today.  Tomorrow I'll finish the other. 

[Rob Babcock]

I didn't know you could get panels of it so large!  Very cool.   Shipping is brutal (by their calculator) though.

[JonnyFive]

A local audio enthusiast suggested I call around to insulation companies to see if they could supply the panels rather than having them shipped.  I found someone that saved me $100/box on four packs of 8' x 4' Owens Corning 2" Select Sound rather than buying them online.  So definitely check locally.

[JWL.GIK]

703 is a mostly awesome material to use. Some people are sensitive to its odor when you first get it, likely a byproduct of the manufacturing stage using formaldehyde. If you have a formaldehyde allergy it can affect you. In such cases (703 has a smell to it), airing out the 703 for a while before making the traps can eliminate the odors & problems.

If you use adhesive (like contact spray adhesive) to attach the cloth to the fiberglass it can help seal it up a bit more too. Be careful when making them, wear gloves, long sleeves, and maybe a breathing mask.