Lethal Concentration(50) (LC50)
A calculated concentration of a chemical in air to which exposure for a specific length of time is expected to cause death in 50% of a defined experimental animal population.

Adenocarcinoma
Adenocarcinoma of the lung is a type of lung cancer. Like other cancers, adenocarcinoma is the growth of abnormal cells. These cancerous cells multiply out of control, and form a tumor. As the tumor grows, it destroys parts of the lung. Eventually, the tumor's abnormal cells can spread (metastasize) to other parts of the body, including the brain.

Immediately Dangerous to Life or Health (IDLH)
The maximum environmental concentration of a contaminant from which one could escape within 30 minutes without any escape-impairing symptoms or irreversible health effects.

Stage 2 Mesothelioma
Stage 2 mesothelioma has spread to both layers of the pleura on one side of the body only

Asbestos Containing Material (ACM).
Any material or product that contains more than one percent asbestos.

Suspect material
Building material suspected of containing asbestos, e.g., surfacing material, floor tile, ceiling tile, thermal system insulation, and miscellaneous other materials.

Fibrosis
A condition marked by the increase of connective, fibrous tissue.

Crocidolite
A type of asbestos in the amphibole group; it is also known as blue asbestos.

Abatement
Removal or controlling release of asbestos fibers. Includes operations and maintenance (O & M), encapsulation, enclosure, and removal.

Bulk Sample
A sample of suspected asbestos-containing material that is obtained from a building to be analyzed microscopically for asbestos content. Bulk sample analysis can be part of a process to assess the hazard from asbestos in a building.