What is the primary type of asbestos used in the U.S.?

• A. Chrysotile
• B. Amosite
• C. Crocidolite
• D. Tremolite

Answer: (A)

The most common asbestos type used in the United States is chrysotile, the serpentine form. Its fibers are curly and flexible, which made it easy to incorporate into a wide range of building materials and products such as insulation, roofing, and cement. Because chrysotile was abundant, easier to work with, and historically supplied, it dominated asbestos use in the U.S., comprising the vast majority of asbestos-containing materials produced and installed.

The other forms—amosite, crocidolite, and tremolite—are amphibole asbestos with straight, needle-like fibers that tend to be more durable and more hazardous when inhaled. They were used less widely and are now tightly regulated, which is why they don’t represent the primary type historically used in the U.S.

So, chrysotile is the primary type associated with U.S. asbestos use.