These products were made with the purpose of retaining their initial form in situations where extreme heat was involved on a constant basis. Most of these cases were revolving around the manufacturing of materials like aluminum or for applications around heating systems.
The people that suffered the most from the asbestos exposure regarding refractory materials were the ones involved in their manufacturing as they were constantly working in an asbestos contaminated environment. Applied refractory products posed a lower risk of asbestos exposure as they had an increased durability, but there were cases where they got damaged and the asbestos fibers were put in a friable state. You could have been exposed if: