Photographs of asbestos fragments (above) & fibers under the microscope
Tremolite asbestos micro-photographs
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This page illustrates what asbestos fibers or fragments may look like under the polarized light microscope. This document assists building buyers, owners or inspectors who need to identify asbestos materials (or probable-asbestos) in buildings by simple
visual inspection.
We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products
to permit identification of definite, probable, or possible asbestos materials in buildings.
While an expert lab test using polarized light microscopy may be needed to identify the specific type of
asbestos fiber, or to identify the presence of asbestos in air or dust samples, many asbestos-containing building products
not only are obvious and easy to recognize, but since there were not other look-alike products that were not asbestos, a visual identification of this material can be virtually a certainty in many cases.
ASBESTOS UNDER THE MICROSCOPE - Micro photographs of Asbestos
Here are two photographs showing what a sample of asbestos ceiling fireproofing (tremolite asbestos) looks like in
our lab microscope using polarized light microscopy (PLM).
Notice that
in the first photo you see long very thin multi-fibrous filaments - asbestiform tremolite.
Each filament is less than one micron in diameter. In the second photograph
you'll observe non-fibrous granular particles, many less than one micron in diameter as well -
non-asbestiform tremolite. [McCrone]
This asbestos sample was collected from slabs of nearly pure tremolite asbestos which was
used as Fireproofing containing Asbestos in
a commercial building.
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06/07: thanks for photographs of transite asbestos heating ducts, courtesy of Thomas Hauswirth, Managing Member of
Beacon Fine Home Inspections, LLC and (in 2007) Vice President, Connecticut Association of Home Inspectors
Ph. 860-526-3355 Fax 860-526-2942 beaconinspections@sbcglobal.net
Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
Enviro-Scare: Electric Power Lines, Electromagnetic Fields, Cancer Risk, & "Enviro-Scare" - The Normal Curve Cycle of Public Fear of Environmental Issues
Dust from the World Trade Center collapse following the 9/11/01 attack: the lower floors of this building contained spray-on fire-proofing asbestos materials.
Asbestos Information Links: Asbestos Detection, Testing, Recognition, Hazards, Field Photos, and Information Sources, including
health-related links such as legal services and information about mesothelioma and other cancers.
Asbestos Identification and Testing References
Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed
the basis for current work by asbestos identification laboratories.
Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone
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