What is Asbestos?

What is Asbestos?

Asbestos is the name of a group of highly fibrous minerals with separable, long, and thin fibers. Separated asbestos fibers are strong enough and flexible enough to be spun and woven. Asbestos fibers are heat resistant, making them useful for many industrial purposes.

Asbestos has been used commonly in a variety of building construction materials for insulation and as a fire-retardant. Because asbestos fibers are resistant to heat and most chemicals, they have been mined for use in over 3,000 different products, including roofing materials, brake pads, and cement pipe often used in distributing water to communities. Today, asbestos is most commonly found in older homes, in pipe and furnace insulation materials, asbestos shingles, millboard, textured paints and other coating materials, and floor tiles.

Elevated concentrations of airborne asbestos can occur after asbestos-containing materials are disturbed by cutting, sanding or other remodeling activities. Improper attempts to remove these materials can release asbestos fibers into the air in homes, increasing asbestos levels and endangering people living in those homes.

Asbestos can be positively identified only by a trained analyst using a specialized microscope.

Where Asbestos Hazards May Be Found In The Home

Some roofing and siding shingles may have asbestos in them.

Houses built between 1930 and 1950 may have asbestos as insulation.

Asbestos may be present in textured paint and in patching compounds used on wall and ceiling joints. Their use was banned in 1977.

Older products such as stove-top pads may have some asbestos compounds.

Walls and floors around woodburning stoves may be protected with asbestos paper, millboard, or cement sheets.

Asbestos may be found in some vinyl floor tiles and on the backing on vinyl sheet flooring and adhesives.

Hot water and steam pipes in older homes may be coated with an asbestos material or covered with an asbestos blanket or tape.

Oil and coal furnaces and door gaskets may have asbestos insulation.

Asbestos in Drinking Water

In 1974, Congress passed the Safe Drinking Water Act. This law requires EPA to determine safe levels of chemicals in drinking water which do or may cause health problems. These non-enforceable levels, based solely on possible health risks and exposure, are called Maximum Contaminant Level Goals.

The MCLG for asbestos has been set at 7 million fibers per liter of water (M.L.) because EPA believes this level of protection would not cause any of the potential health problems described below.

Based on this MCLG, EPA has set an enforceable standard called a Maximum Contaminant Level (MCL). MCLs are set as close to the MCLGs as possible, considering the ability of public water systems to detect and remove contaminants using suitable treatment technologies.

The MCL has also been set at 7 M.L. because EPA believes, given present technology and resources, this is the lowest level to which water systems can reasonably be required to remove this contaminant should it occur in drinking water.

Asbestos (Amosite) Viewed Under Microscope.jpg

These drinking water standards and the regulations for ensuring these standards are met, are called National Primary Drinking Water Regulations. All public water utilities must abide by these regulations.