of Heated Vermiculite
What is vermiculite?
is a naturally occurring mica-like mineral that has the unusual
property of expanding into worm-like accordion shaped pieces when
vermiculite becomes a light-weight, fire-resistant, absorbent, and
odourless material. These properties allow vermiculite to be used
to make numerous products, including attic insulation. Vermiculite
attic insulation is a pebble like poured in material and is usually
light brown to gold in colour. Sizes of vermiculite products range
from very fine particles to large (course) pieces nearly an inch
long. It is also common to find vermiculite as loose fill insulation in outside wall cavities including concrete block walls."
of Vermiculite Attic Insulation
Vermiculite is also used in acoustic
finishes, concrete mixes for swimming pools, agricultural and horticultural
products, and in industrial products (i.e. brake shoes and pads,
drilling mud, furnaces, and insulation blocks).
Why is vermiculite
insulation a problem?
has been an established commercial commodity for well over 50 years,
and is currently used throughout the world. Of concern is the vermiculite
ore produced by the Libby Mine in Montana from the 1920's to 1990.
During this period, the Libby Mine accounted for more than half
the worldwide production of vermiculite. One tenth of the Libby
Mine production was shipped to Canada.
the vermiculite produced at the Libby Mine was found to be contaminated
with asbestos and asbestos like fibers. Workplace exposure to these
fibers caused a serious health problem with local miners and millers,
as well as some downstream workers.
The Libby Mine
produced vermiculite was sold in Canada under the name Zonolite
Attic Insulation and possibly other brands. The type of asbestos
contamination present is tremolite, a particularly hazardous form of asbestos and the concentration ranges
from 0.3% to 7%.
I have vermiculite
insulation in my building - does it contain asbestos?
made from vermiculite ore produced by the Libby Mine were not widely
used after the mid-1980's and have not been on the market in Canada
for more than 10 years. Not all vermiculite produced before 1990
contains asbestos fibers. However to be safe and in the absence
of evidence to the contrary, if your building has older vermiculite
insulation, it is reasonable to assume it contains asbestos.
If you wish
to test your vermiculite insulation for the presence of asbestos,
have a professional collect three samples for laboratory analysis.
The samples should be collected and analyzed following USEPA method
EPA / 600 / R-04 / 004 (Sampling and Analysis of Fibrous Amphibole
in Vermiculite Attic Insulation).
is mined at facilities which are asbestos free or have low levels
of asbestos contamination in the finished material.
I do if I have vermiculite attic insulation?
NOT DISTURB IT. Any disturbance has the potential to release asbestos
fibers into the air. Vermiculite insulation that is contained and
not disturbed poses very little risk to building occupants. If you
decide to remove vermiculite insulation from your building, speak
to a trained and qualified asbestos removal professional. NEVER
attempt to remove the insulation yourself.
on minimizing your exposure to asbestos in vermiculite can be found
on the Health Canada and USEPA websites. Alternatively, you can
contact your local Power Environmental representative.
How can Power
Environmental help me?
Environmental is a leading provider of environmental services involving
hazardous materials and indoor air quality. These services include
investigations, remediation and contracting. We have pioneered the
development of low cost removal vermiculite techniques involving
the use of industrial power vacuums and high efficiency cloth filter
bags. All work is done in accordance with Ministry of Labour Regulations
using certified crews specially trained for this type of work.