Regulated Asbestos

Regulated asbestos refers to the specific asbestos minerals that laws and agencies officially control. In the United States this generally means six fiber types: chrysotile, amosite, crocidolite, tremolite, actinolite, and anthophyllite. Materials containing more than a set percentage of these fibers fall under rules for handling, removal, and disclosure.

Origin

The regulatory list took shape through OSHA, the EPA, and the Asbestos Hazard Emergency Response Act (AHERA) during the 1970s and 1980s, which defined asbestos for legal purposes as those six mineral types.

Significance in Asbestos Context

For patients, the regulatory definition matters because it can leave gaps. Some hazardous fibers, such as certain forms of tremolite or the amphiboles found in Libby, Montana, weren't always fully captured, and products falling below a threshold percentage could escape the "asbestos-containing" label while still causing disease. This narrow definition sometimes let companies claim their products were asbestos-free. Records showing a product's actual mineral content, not just its regulatory label, can matter to a claim.

Example Sentence

The defense argued the flooring wasn't "regulated asbestos," but testing showed it contained chrysotile above the one-percent threshold.

Related Terms

AHERA, Asbestos-Containing Material, Chrysotile, Tremolite, OSHA, Libby Amphibole

Notes

• Don't assume a product labeled asbestos-free was safe; the label may reflect the regulatory definition rather than the actual fiber content.
• Ask whether independent testing of a product or material identified fibers outside or below the regulated thresholds.
• Preserve product samples and packaging; actual mineral content can matter more than how a product was classified.