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Photographic gallery.  Thousands of particles under the microscope.
Glass Fiber and Phytolith

Glass fiber, as used here, is any isotropic fiber with a cross-section consistent with formation by surface tension, sharp or abrupt terminations, and with visible inclusions limited to elongated bubbles. Glass fiber is a major cause of Building Related Illness. The paper below is from the Indoor Air 2011 Conference in Austin, Texas, paper 81.

Health Complaints and Environmental Glass Fiber Acoustic ceiling tile that contains glass fiber can be divided into two basic groups by their gross appearance. The body of the tile is either compact and gray or loose and yellow. The gray tile exhibits the greatest variability in composition, from nearly 90% glass fiber to about 10% glass fiber. The other materials in the body of the tile may include perolite, paper fiber, clay, calcite, glass shot, glass blebs, and asbestos. Glass fiber from acoustic ceiling tile is identified by the other materials still attached to it. Clear epoxy binder, sodium silicate, or similar clear binder containing small particles of calcite filler and binding the glass fiber to any of the other possible materials used to make these tiles identifies the glass as coming from acoustic ceiling tile.

Acoustic Ceiling Tile Acoustic Ceiling Tile Worn Edge 2 Acoustic Ceiling Tiles Acoustic Ceiling Tile Cropped Acoustic Ceiling Tile Acoustic Ceiling Tile Acoustic Tile Gray Acoustic Tile Gray Acoustic Tile 2 Amosite and Glass Acoustic Tile The yellow bodied acoustic ceiling tile that contains glass fiber is composed of glass fiber and yellow phenolic resin. The amount of resin and the amount of mineral filler used in the resin varies from one grade to another and from one manufacturer to another. Glass fiber from yellow bodied acoustic ceiling tile can often be distinguished from other yellow phenolic bound glass fiber. Yellow phenolic bound glass fiber from sound board in the HVAC system is generally covered with small impacted particles of natural minerals, soot, pollens and other airborne particles. Yellow phenolic bound glass fibers from blanket insulation typically contain much less mineral filler in the resin. Yellow phenolic bound glass fiber from cubicle divider panels tends to contain much more yellow resin than the yellow bodied acoustic ceiling tile. See the "Glass Fiber" section of the gallery for examples of all these materials.

Ceiling Tile 200X Glass Fiber Acoustic Yellow Phenolic Ceiling Tile 100X Phenolic Ceiling Tile 100X AcousticTile

A common structure for a cubicle divider consists of a metal frame supporting a resin stiffened glass
fiber pannel. The glass fiber pannel is then covered with a thin loose glass fiber blanket and an outer
layer of cloth. Glass fiber from the cubicle divider is heavily coated with heavily filled yellow or orange
phenolic resin. The deterioration of the glass fiber pannel is typically due to the pannels use as a
pincushion or to other forms of mechanical damage.

Glass Fiber With Filled Resin Glass Fiber With Filled Resin Glass Fiber With Filled Resin Glass Fiber With Filled Resin Glass Fiber With Filled Resin Glass Fiber from Partition Pad The HVAC system is a common source of glass fiber in indoor office and school environments. These glass fibers are generally coated with particles impacted onto their surfaces that mark them as having been exposed to a moving air stream. These impacted particles typically have diameters smaller than that of the fiber on which they rest. The color of the resin associated with glass fiber from the HVAC system varies. It may be yellow, orange, red, green, gray, or black. The same "soundboard" may have more than one color of resin on it. One common combination is a yellow resin used for the bulk of the glass fiber mat with a coating of black, mineral-filled resin on the outer surface of the panel. The resin used for the soundboard panels is generally heavily filled with clay or silica.

HVAC Soundboard HVAC Insulation HVAC Insulation HVAC Flex-Duct Insulation HVAC Black 80X HVAC Insulation HVAC Insulation HVAC Insulation HVAC Insulation HVAC Insulation Winsill Vent GF 2 Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Glass Fiber, HVAC System Thermal blanket insulation is made from glass wool with a small amount of resin to bind the fibers together in order to maintain loft. The resin is typically yellow, pink, or colorless (white). The fibers tend to be clean other than the presence of the resin when found in environmental samples though is some instances, where they have been exposed to air flow, they can become coated with particles and look similar to ventilation system glass fibers.

Pink Blanket Insulation Pink Blanket Insulation Pink Blanket Insulation Glass Fiber Blanket Insulation Glass Fiber, Pink Glass Fiber, Yellow Glass Fiber, White Blanket Glass Fiber, White Blanket Glass Fiber, White Blanket

Exposed to Building Fires

Glass Fiber from Apartment Building Fire Glass Fiber from Apartment Building Fire Glass Fiber from a House Fire Glass Fiber from a House Fire

Glass fiber from the tape used to smooth the joint between two panels of drywall is often found following construction but it is rarely at levels that could result in health complaints by itself. It often contributes to the overall glass fiber loading in buildings as as result of construction.

Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Gypsum Board Glass Fiber Glass Fiber Bulk Insulation Glass Fiber Bulk Insulation Glass Fiber Bulk Insulation Glass Fiber Bulk Insulation Mineral Wool 100X 1 Mineral Wool 100X 1 Rock Wool 100X 1 Glass Fiber Bulk Insulation Glass Fiber Bulk Insulation

Recycled Glass Fiber as Blown-in Insulation

Recycled glass fiber is often used as blown-in "green" insulation. It is "green" only in the environmental sense. The glass fiber is thermally treated to clean it which results in the old binder being charred.

Recycled Glass Fiber Bulk Insulation Recycled Glass Fiber Bulk Insulation Recycled Glass Fiber Bulk Insulation Recycled Glass Fiber Bulk Insulation HEPA Filter Fiber HEPA Filter Fiber

Cutting glass fiber composite materials creates a significant amount of free, short glass fiber. Individuals doing this work seldom complain about the effects of exposure but the glass fiber dust they may carry into other environments may result in healt complaints by others now exposed. One example is glass fiber from removing fiberglass casts in a clinic. This dust can result in complaints by others working in the clinic if the dust is not adiquitely controlled.

Fiberglass Sawdust Fiberglass Sawdust from Removing a Medical Cast Fiberglass Sawdust from Removing a Medical Cast Asbestos Substitute Gas Fireplace Glass Fiber Kiln Glass Fiber Kiln Glass Fiber Kiln Glass Fiber Kiln Glass Fiber Kiln Glass Fiber Kiln Glass Fiber Gas Turbine Exaust Glass Fiber Gas Turbine Exaust Glass Fiber Gas Turbine Exaust Glass Fiber Shuttle Bay B-Cloth Glass Fiber From The Space Shuttle Thermal Tiles

Identifying Glass Fiber

Glass fiber can only be acurately identified using a polarized light microscope and by being aware of the possible interferences. The images below provide examples demonstrating the importance of polarized light and natural substances that can be confused with man-made mineral fiber.

Bird Feather Barbules

Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like

Plastic Fiber

Glass Fiber Look-A-Like

Phytoliths

Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like

Diatoms, etc.

Glass Fiber Look-A-Like

Sponge Spicules

Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like Glass Fiber Look-A-Like

Insect Hair (Setae)

Glass Fiber Look-A-Like