ACM

ACM stands for asbestos-containing material: any material containing more than one percent asbestos by weight, the threshold OSHA and EPA both use. It’s the umbrella term that the more specific categories sit under.

ACBM is the AHERA subset for materials found in buildings. RACM is EPA NESHAP’s term for the friable ACM (and non-friable ACM likely to become friable) that triggers notification and work-practice rules. Whether a given piece of ACM is regulated at a given moment depends on its category, its condition, and how it will be disturbed.

ACM is grouped as friable or non-friable, and non-friable ACM is further split into Category I (packings, gaskets, resilient floor coverings, asphalt roofing) and Category II (everything else, such as transite board). The category drives how the material may be handled and disposed of.