I use Kaowool and once when I was repairing a furnace with Fiberfrax (a Kaowool clone ?) and saw very small fibers floating in the air. So I put on my respirator. In some Youtube videos of furnace builders I also see recommendations for respirator or face mask when handling bare Kaowool and it can only be used safely when it is coated with Satanite or Fermit or another mortar. Is that really true ?
That has always been my understanding. I usually just go outside and try not to notice all the airborne fibers flying around if I have to cut some up (not very often), and I keep the rest of it bagged up in my shed, not in the house. Although some brands of "body soluble" ceramic fiber blanket are supposedly safe. I would always coat it anyhow even if it was just to protect the blanket from tongs and direct flames. Jeff
If you read the MSDS for the bio-soluble stuff, although there's no mention of long term effects, it's still listed as a "respiratory irritant" which I read as, "it won't kill you but it's still unpleasant". So with either type, it's a good idea to do whatever is necessary to avoid breathing the fibers.
If I worked with the stuff everyday, I'd be a bit more concerned. Today I had the pleasure of working with MEK. There is a chemical that is perfectly MISERABLE! This stuff supposedly attacks your liver and it dissolves gloves with a quickness so not much choice but to push it on a rag by hand. I only have to deal with it once or twice a year, but I really lean on my guys because they practically take baths in this stuff all the time! Exposure to hazardous stuff is inevitable, but risk can be mitigated by frequency or take it outside like Jeff. I have to deal with Silica doing shell work I usually have a dust mask on. Far from perfect, it drastically cuts down what I inhale. A respirator really sucks when it's 100degrees!
MEK is pure evil! I have to use it regularly but didn't know about the liver thing. Kaowool is known for it's issues. One of those things similar to asbestos in as much as someone can work with it for years and get away with it yet another poor sole cops it from a small exposure.
There are no documented lung issues in humans related to industrial exposure to kaowool. It has been studied for a decade or more. There was trend toward COPD increase in smokers. But, if you choose to inhale documented severe carcinogens by smoking, kaowool is the least of your worries: The way virtually all of us use this product it is extremely unlikely to cause serious harm. Exposure to the dust can be annoying. Denis
@Peedee I don't think we need to break out the A-word. Not all dusts are equal, and *cough*asbestos*cough* are among the worst. IIRC it has the ability to crumble into finer and finer needle-like fibers, and those are very good at causing irritations. They are also completely non-soluble, so they're there to stay. I believe silica has a similar action due to it's crystalline nature. Kaowool is closer to glass wool in that it should be glassy. And amorphous materials tend to crumble into more rounded (less irritating) shapes. But unless it's soluble it will still be bad for you. So common sense advocates some protection when dust is formed. I would assume coated wool to be fairly safe.
Please don't take me for an authority on the subject, it's been 25 years since I worked on asbestos and occupational hazards. One think to bear in mind is that high temperature aging can allow the glass to turn crystalline. So old kaowool might be worse than fresh.
It seems simple to me, hazardous or not, prudence and common sense dictate taking appropriate steps to protect yourself and others from airborne fibers and/or crystals.
