What are the Categories of Asbestos-Containing Materials?

To qualify as an asbestos-containing material (ACM) under the law, a product must contain more than 1 percent asbestos, either by weight for bulky materials or by area for flat ones. Regulations distinguish between friable ACM (can be reduced to dust by the crushing of hands) and non-friable ACM (cannot be crushed or damaged so easily).

There are two categories within the group of non-friable ACMs. Category I distinguishes material that has become friable because of whether, aging, or force and can release asbestos fibers into the air. Category II is everything else non-friable. Category II ACMs can also come under regulation if they are cut, sanded, or scraped to the point where they produce dust and presumably airborne asbestos fibers. During the course of renovation or demolition, both of these categories become "regulated asbestos-containing materials" (RACM).

What to Look For

It is not easy to identify asbestos-containing materials in use. But it is safe to assume any material of an appropriate age was likely made with asbestos. To really know if a material contains asbestos, it is best to hire a professional to sample the material in question, who then sends collected samples to a laboratory certified by the Environmental Protection Agency for examination. Then an experienced technician uses a polarized microscope to located asbestos fibers.