What does the term "settled dust" refer to in the context of air monitoring?

In the context of air monitoring, "settled dust" specifically refers to asbestos fibers that have settled onto surfaces rather than remaining airborne. Understanding this concept is crucial for asbestos monitoring because settled dust can pose a significant risk if disturbed, potentially releasing asbestos fibers back into the air where they can be inhaled.

This term is particularly important in assessing the safety of an environment where asbestos is present. Monitoring settled dust helps in determining the presence or absence of harmful fibers in areas that might be overlooked if only airborne fibers are considered. It provides a more comprehensive understanding of potential exposure risks because even if air samples show low levels of airborne asbestos, settled dust may still harbor significant amounts of it on surfaces.

In practical scenarios, when conducting inspections or air monitoring, professionals must evaluate both airborne asbestos and settled dust to assess the full extent of contamination and implement appropriate remediation actions if necessary.