How is friable material defined in relation to asbestos?

Friable material, in the context of asbestos, is defined as material that can be easily crumbled or pulverized by hand pressure when dry. This definition is crucial because it highlights the hazardous nature of such materials, as they can release asbestos fibers into the air when disturbed. Friable asbestos materials pose a significant health risk because inhalation of these airborne fibers can lead to serious respiratory diseases.

The other options do not accurately describe friable materials. For instance, materials that are solid and unbreakable under pressure would be considered non-friable, indicating they are less likely to release fibers into the air. Similarly, a material that is resistant to environmental breakdown typically does not produce harmful particles that could become airborne. Lastly, the ability to absorb moisture is not a defining characteristic of friable materials; while some friable materials may contain moisture, it is not a factor in the definition of their friability. Thus, understanding the specific meaning of friable materials is essential for asbestos safety and regulations.