When is asbestos a hazard?
Asbestos is not always an immediate hazard. In fact, if asbestos can be maintained in good condition, it is recommended that it be left alone and periodic surveillance performed to monitor its condition. It is only when asbestos containing materials (ACM) are disturbed or the materials become damaged that it becomes a hazard. When the materials become damaged, the fibers separate and may then become airborne. In the asbestos industry, the term "friable" is used to describe asbestos that can be reduced to dust by hand pressure. "Non-friable" means asbestos that is too hard to be reduced to dust by hand. Non-friable materials, such as transite siding and floor tiles, are not regulated provided it does not become friable. Machine grinding, sanding and dry-buffing are ways of causing non-friable materials to become friable.