Asbestos-containing packings, gaskets, resilient floor covering, and asphalt roofing products containing more than 1.0% asbestos as determined by polarized light microscopy are categorized as which?

• A. Category I nonfriable asbestos-containing material (ACM)
• B. Category II nonfriable ACM
• C. Friable ACM
• D. Asbestos Containing Materials (ACM)

Answer: (A)

Asbestos-containing materials are classified by how easily they release fibers (friability) and how much asbestos they contain. If a material is not easily crumbled by hand and it contains asbestos above a threshold (determined by testing, such as polarized light microscopy), it is categorized as nonfriable ACM. The items listed—packing and gasket materials, resilient floor coverings, and asphalt roofing products—are typical nonfriable products. When intact, they don’t crumble easily, so they are placed in the Category I nonfriable ACM category. This distinguishes them from friable ACM, which can be crumbled or powdered with little effort and poses a higher immediate release risk, and from other nonfriable ACM categories that cover materials with different tendencies to release fibers under disturbance. Therefore, these materials are best classified as Category I nonfriable ACM.