Anthophyllite
A type of asbestos in the amphibole group; it is also known as azbolen asbestos.

Asbestosis
A progressively restrictive fibrosis of the lung and is recognized as a disabling and fatal occupational disease.

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.

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

Friable asbestos
Any material containing more than one percent asbestos, and that can be crumbled or reduced to powder by hand pressure. (May include previously non-friable material which becomes broken or damaged by mechanical force.)

Stage 1 Mesothelioma
Stage 1 mesothelioma affects one layer of the pleura only. It may have grown into the covering of the heart (pericardium) and the diaphragm

Asbestos
A general term applied to certain polysilicate fibrous minerals displaying similar physical characteristics although differing in composition. The most common asbestos mineral (over 95% of U.S. production) is chrysotile, a variety of serpentine, a metamorphic mineral.

RACM
Regulated Asbestos-Containing Material is (a) friable asbestos material, (b) Category I non-friable ACM that has become friable, (c) Category I non-friable ACM that will be or has been subjected to sanding, grinding, cutting or abrading, or (d) Category II non-friable ACM that has a high probability of becoming or has become crumbled, pulverized, or reduced to powder by the forces expected to act on the material in the course of demolition or renovation operations.

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

Excursion Limit (EL)
1 Fiber per cubic centimeter averaged over a 30 minute sampling period.