Categories of Asbestos-Containing Materials

There are only six asbestos-containing products, also known as asbestos-containing materials (ACM), that are considered illegal to use.

The first thing to know is what qualifies a material as "asbestos-containing."

If a material contains one percent or more of asbestos fibers, either by weight or by total surface area (like roofing felt or flooring), then that material is illegal to use under federal law.

The difference between asbestos-containing materials is whether or not they are "friable." Friable ACM can be crumbled, pulverized, or reduced to powder by the pressure of a human hand. This becomes a concern because asbestos fibers are dangerous when broken loose and begin floating in the air. The fibers become loose when the surrounding material is crumbled away. A non-friable ACM can also contain more than one percent asbestos, but it cannot be pulverized under hand pressure and therefore causes little to no harm. It is harder to release the fibers and create a danger to health. However, there remains room for non-friable ACM to be dangerous and therefore falls under government regulations.

There are two categories of non-friable ACM. Materials in Category I are non-friable because their surrounding materials are flexible and durable, which include packings, gaskets, resilient floor covering, and asphalt roofing products. Everything else non-friable is Category II.

Both friable and non-friable materials fall under the definition of "regulated asbestos-containing material" (RACM). The regulations cover:

• All friable asbestos-containing material
• Category I non-friable asbestos materials that have become friable for whatever reason - age, exposure to sunlight, or other forces that have broken down the material
• Category I non-friable asbestos materials that will be or have been subjected to sanding, grinding, cutting, or abrading become as dangerous as friable ACMs
• Category II non-friable asbestos materials that have a high probability of becoming, or that have already become, crumbled, pulverized, or powdered by force

Any material that contains asbestos fibers can create a dangerous atmosphere of airborne minerals. By its basic nature, how it has been handled, or because it has been or will be broken up, it is likely to release those fibers and potentially create an atmosphere that is dangerous to human health. The danger of asbestos occurs when the material is crumbled, pulverized, or powdered, and these fibers can hang in the air for weeks if they are not contained at the same time. The remaining debris can also continue to spread fibers into the air if it is not kept contained all the way to a disposal site. Containment is the main focus of regulation.