Physical Plant Services: Asbestos Containing Material (ACM) Image Page #1
This is unmilled mineral asbestos (chrysotile). Various forms of asbestos were widely used in many products throughhout the United States since the early part of the century until the early 1980s. Asbestos was used because of it's high tensile strength, flexibility, and resistance to thermal, chemical, and electrical conditions.
Contrary to popular belief, asbestos or asbestos containing material (ACM) has not been banned (except for certain applications) and may still be found in manufactured or imported products and building materials. Although health concerns, legal liability, and regulatory requirements have largely stifled most manufacture or use of ACM in the U.S., many other countries still use asbestos and/or otherwise export asbestos.
Asbestos is generally defined as being friable (definition: can easily be turned into a dust with finger pressure), or non-friable.
Unmilled mineral asbestos (chrysotile).
Thermal System Insulation (TSI):
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Example of highly friable thermal system insulation (TSI). This particular type, often called "mag" insulation, was used to insulate pipes. At UWM, we normally find mag on high-temperature utilities such as steam or condensate lines. This sample contains both chrysotile and amosite asbestos. This particular sample has long visible fibers, but some mag insulation doesn't. As seen in this photo, mag insulation is highly friable and can result in significant exposure if disturbed. Please click on the thumbnail for a larger image. |
Example of common asbestos thermal system insulation (TSI), similar in appearance to gray, wrapped paper or cardboard.

Though similar in appearance to the TSI above, the insulation pictured below is non-ACM. It was obtained from another building. In this particular example, there was no ACM tarred inner layer. So, is there a way to tell the difference simply by appearance? No, you must have it analyzed.

The gray corrugated, cardboard-like material pictured below is AirCell (or Air-O-Cell) asbestos insulation.
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Instance where new fiberglass insulation was applied directly over existing asbestos TSI. Use caution when working on any unlabeled material, particularly in areas where we have both ACM insulation side-by-side with new insulation. If in doubt, assume the material is ACM. This 'insulation repair job' was most likely done prior to the establishment of our asbestos management program (i.e., pre-mid 1980s). |
High Temperature Applications:
| Asbestos block insulation is often applied to high temperature applications, like the exhaust stacks of our building emergency generators. At UWM, application of this material occurred well into the late 1970s. Sample #41223K61 contains approximately 10% chrysotile and 30% amosite asbestos.
The bottom photo shows where a non-authorized (contractor) worker cut into the asbestos insulation when installing a new gas and water line for this generator unit resulting in an asbestos release and exposure hazard. This occurred even though the insulation was clearly placarded with warning labels (as shown). This act was in violation of OSHA and state regulations and in disregard to acceptable exposure control techniques. |
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Transite and Transite-like Products:
Example of transite board. This variety is similar in appearance to common pegboard, except transite is usually gray and very dense. The perforated variety is often used in acoustical applications such as in music rooms, phone booths and auditoriums. Transite is a Category II waste.
. The images below are of a laboratory bench top (transite) with black laminate surface. Note the visible fibers in the asbestos bench sample. The small sample on top is from a stone bench top. Transite is a Category II waste. Superficially, the transite and stone bench tops look identical due to the black laminate surface. UWM has both varieties. As with other Category II materials, specialized work practices and disposal requirements exist for ACM laboratory bench tops.
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Plaster:
Pictured is plaster sample #80807K19; white finish coat over brown/base coat applied to wire lathe. This 1920s vintage plaster meets the definition of asbestos containing material (ACM), and becomes friable if it is disturbed. Note the visible fiber bundle at 7.5 mm. Many acoustical plasters are also ACM.

Several buildings at UWM have acoustical plaster similar to the sample below. In most cases, the asbestos layer is the thin (1/8") textured surface layer; the base coat (brown-coat) pressed into wire lathe must also be tested for asbestos content.

Ceiling Tile:
Although rare at UWM, ceiling tile may also contain asbestos. This tile has both chyrsotile and amosite fibers (sample #60423K08, less than 10% each). Click on the thumbnail for a larger view (58Kb).

Flooring, Floor Tile and Floor Underlayment:
Example of industrial sand floor underlayment and nine-inch asbestos composite floor tile in the Kenilworth building. We believe the purpose of the underlayment was for vibration dampening and noise reduction in this former factory building, built 1914, by the Ford Motor Company. The underlayment is approximately 1" thick. This material contains approximately 10% chrysotile asbestos and is applied directly over concrete. Asbestos floor tile is applied over the underlayment.










