Of concern is zonolite attic insulation.
Vermiculite asbestos attic insulation.
Vermiculite attic insulation is a pebble like pour in product and is usually light brown gray or gold in color.
The vermiculite from libby is part of the longest man made environmental disaster in american history.
One common brand was called zonolite.
Consider this statement from research titled zonolite attic insulation exposure studies where even the suggested method for removal by the manufacturer grace created a very unsafe condition.
As long as this kind of vermiculite based insulation remains undisturbed behind intact walls or in attic spaces and does not become airborne it should not be a concern.
However the vermiculite used in about 70 percent of the zonolite product came from the montana mine mentioned a moment ago.
That s good news because most zonolite a type of vermiculite insulation falls into that category.
However some vermiculite insulation contained asbestos fibres which can cause problems if inhaled.
It was mined there for more than 50 years ending in 1990.
This insulation was sold in canada under the name of zonolite and was extracted from the libby mine in montana usa.
Once vermiculite is disturbed millions of asbestos fibers become airborne.
The epa says that vermiculite insulation which is the pebbly stuff found in attics of many older homes is only risky if it contains more than one percent asbestos.
The insulation which was known by the brand name zonolite is most often found in residential attics.
The asbestos found in vermiculite is extremely friable and is the most dangerous type amphibole of asbestos.
What made the libby vermiculite so dangerous was its proximity to asbestos deposits.
Vermiculite in and of itself is not dangerous.
When heated to a high temperature flakes of vermiculite expand as much as 8 30 times their original size.
It may have shiny flakes and or small accordion like pieces see photos above.