Asbestos Program

Asbestos is a mineral composed of silicon, oxygen, hydrogen, and various metal cations (positively charged metal ions).

There are many varieties of asbestos: the three most common are chrysotile, amosite, and crocidolite. Chrysotile fibers are pliable and cylindrical, and often arranged in bundles. Amosite and crocidolite fibers are like tiny needles. Unlike most minerals, which turn into dust particles when crushed, asbestos breaks up into fine fibers that are too small to be seen by the human eye. Often individual fibers are mixed with a material that binds them together, producing ACM.

Although asbestos was first used in this country in the early 1900's, it was not until the 1940's that its use became widespread. Manufacturers and builders began incorporating asbestos into their products for several reasons: It is "strong yet flexible, and it will not burn. It conducts electricity poorly, and insulates effectively. It also resists corrosion. Finally, compared to the few other available materials that combine these traits, it is inexpensive.

For these reasons, use of asbestos in a variety of commercial products and in constructing or renovating buildings exploded in the years following WWII and continued for the next thirty years. In the construction industry, ACMs were used for fireproofing, soundproofing, insulation, and decoration. Many commercial products, such as plastics, paper products, brake linings, and textile products, also contained asbestos. Today the final Asbestos Ban and Phaseout Rule has stopped the "manufacture, processing and importation" of most asbestos products. But that still leaves the problem of identifying and safely handling all the existing ACMs.

"Suspected" ACMs may be identified by visual inspections, but only instrumental analysis can accurately determine the asbestos content of any given material or product.

Consequently, until a product is tested, it is best to assume that it contains asbestos unless the label or the manufacturer verifies that it does not. To determine the asbestos content of suspected ACMs, the EPA requires the collection of bulk samples, which are subsequently analyzed by polarized light microscopy (PLM). PLM reveals the percent and type of asbestos contained in the samples.

The EPA takes a very reasonable approach to the problem:

EPA's advice on asbestos is neither to rip it all out in a panic nor to ignore the problem under a false presumption that asbestos is "risk free." Rather, EPA recommends a practical approach that protects public health by emphasizing that asbestos material in buildings should be located, that it should be appropriately managed, and that those workers who may disturb it should be properly trained and protected.

That has been, and continues to be, EPA's position. The following summarizes the five major facts that the Agency has presented in congressional testimony:

FACT ONE: Although asbestos is hazardous, human risk of asbestos disease depends upon exposure.

FACT TWO: Prevailing asbestos levels in buildings -- the levels school children and you and I face as building occupants -- seem to be very low, based upon available data. Accordingly, the health risk we face as building occupants also appears to be very low.

FACT THREE: Removal is often not a school district's or other building owner's best course of action to reduce asbestos exposure. In fact, an improper removal can create a dangerous situation where none previously existed.

FACT FOUR: EPA only requires asbestos removal in order to prevent significant public exposure to asbestos, such as during building renovation or demolition.

FACT FIVE: EPA does recommend in-place management whenever asbestos is discovered. Instead of removal, a conscientious in- place management program will usually control fiber releases, particularly when the materials are not significantly damaged and are not likely to be disturbed.

Exposure to asbestos generally occurs via inhalation of asbestos fibers that have been released into the air.

Because asbestos fibers are so small and light, they remain in the air for a long time whenever they are released from an ACM. The fibers also may be ingested if people eat under these conditions.

Deteriorated or damaged ACMs are more likely to release fibers than non-damaged ones. "Friable" ACMs, such as sprayed-on asbestos fireproofing, are more likely to release fibers than "non-friable" ones, such as asbestos containing floor tiles. (An ACM is considered to be fiable if, when dry, it can be crumbled by hand pressure.) However, even non-friable materials can release fibers when sanded, sawed, or otherwise aggressively disturbed. Asbestos cement pipe, for example, can release fibers if crushed or broken when buildings are renovated or demolished. Finally, ACMs in high use areas are more likely to be disturbed and consequently release fibers than those in relatively undisturbed areas.

Once inhaled, asbestos fibers can easily penetrate body tissues. They may be deposited and retained in the airways and lung tissue. Because asbestos fibers remain in the body, each exposure increases the likelihood of developing an asbestos-related disease.

Asbestos related diseases may not appear until [many] years after exposure. A medical examination which includes a medical history, breathing capacity test and chest x-ray may detect problems early. Scientists have not been able to develop a "safe" or threshold level for exposure to airborne asbestos. Ingesting asbestos may be harmful, but the consequences of this type of exposure have not been clearly documented. Nor have the effects of skin exposure to asbestos been documented. People who touch asbestos may get a rash similar to the rash caused by fiberglass.

Among the more serious diseases related to asbestos exposure are asbestosis, lung cancer, and mesothelioma. Cancers in the esophagus, larynx, oral cavity, stomach, colon and kidney may be linked to ingestion of asbestos. More information on lung and other asbestos-related cancers may be gotten from The American Cancer Society. Brief discussions of asbestos-related diseases also are available from the OSHA and EPA websites.

Both the U.S. Environmental Protection Agency and the Occupational Safety and Health Administration (OSHA) are responsible for regulating environmental exposure and protecting workers from asbestos exposure

OSHA's regulations are contained in 29 CFR 1910.1001 for General Industry and 1926.1101 for Construction. The EPA's Worker Protection Rule (40 CFR Part 763, Subpart G) extends the OSHA standards to state and local employees who do asbestos work but are not covered by the standards or by a state OSHA plan. In addition, many State and local agencies have more stringent standards than those required by the Federal government.