Asbestos in Castables
Castables are an aggregate type of cement which can be cast into specific shapes for insulation purposes, particularly where heat and flame pose a danger. As such, these materials might have been found anywhere in buildings or in machinery such as boilers aboard marine vessels, railroad locomotives or military vehicles. In the early and middle 20th century, asbestos fibers were often added to various forms of castables to provide durability, corrosion resistance, and flame resistance.
Numerous small manufacturers sold various asbestos-containing castable materials. The A.P. Green Company produced a line of castable asbestos blocks. The Harbison-Walker Refractories Company produced asbestos-based castables as well.
Hazards Associated with Castable Products
Workers who produced asbestos-containing castables in the factory would have been at the highest risk for asbestos exposure, as they were responsible for mixing raw asbestos fibers into the mix, often with very inadequate safety and respiration equipment. Also at risk were the construction workers, Naval seamen, railroad engineers, and building engineers who used the castable blocks or material in the construction of buildings, ships, trains, and other heavy industrial items. Repair and maintenance workers who handled damaged or worn asbestos castable material could also have been exposed, while demolition or scrapyard workers taking apart buildings or vehicles containing asbestos castable were also open to some exposure risk.Sources
Bowker, Michael. Fatal Deception: The Untold Story of Asbestos (New York: Touchstone, 2003)
N/A. The McGraw-Hill Science & Technology Dictionary. (New York: McGraw-Hill, 2002)