1. What is asbestos?

Asbestos is a group of naturally occurring minerals. The three most common types of asbestos are:

a) chrysotile
b) amosite
c) crocidolite

Asbestos is commonly used as an acoustic insulator, thermal insulation, fire proofing and in other building materials. Asbestos fibers are incredibly strong and have properties that make them resistant to heat. Asbestos is often found in ceiling tiles, pipe and vessel insulation, blown on to structural beams and ceilings, in floor tile, linoleum and mastic.

2. Why is asbestos a hazard?

Asbestos is made up of microscopic bundles of fibers that may become airborne when distributed. These fibers get into the air and may become inhaled into the lungs, where they may cause significant health problems. Researchers still have not determined a "safe level" of exposure but we know the greater and the longer the exposure, the greater the risk of contracting an asbestos related disease. Some of these health problems include:

a) Asbestosis - a lung disease first found in navel shipyard workers. As asbestos fibers are inhaled, they may become trapped in the lung tissue. The body tries to dissolve the fibers by producing an acid. This acid, due to the chemical resistance of the fiber, does little to damage the fiber, but may scar the surrounding tissue. Eventually, this scarring may become so severe that the lungs cannot function. The latency period ( meaning the time it takes for the disease to become developed) is often 25-40 years.

b) Mesothelioma - a cancer of the pleura ( the outer lining of the lung) and/ or the peritoneum ( the lining of the abdominal wall). This form of cancer is peculiar because the only known cause is from asbestos exposure. The latency period for mesothelioma is often 15-30 years.

c) Cancer - caused by asbestos. The effects of lung cancer are often greatly increased by cigarette smoking ( by about 50%). Cancer of the gastrointestinal tract can also be caused by asbestos. The latency period for cancer is often 15-30 years.

Despite the common misconception, asbestos does not cause head-aches, sore muscles or other immediate symptoms. As mentioned above, the effects often go unnoticed for 15-40 years.

3. 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 it’s condition. It’s only when asbestos containing materials 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 reduce to dust by hand. Machine grinding, sanding and dry-buffing are ways of causing non-friable materials to become friable.

4. How are asbestos containing materials maintained?

Friable asbestos can be maintained in place utilizing several techniques. Encapsulation involves applying a thick layer of an encapsulant, much like latex paint, that binds the surface of the material together and prevents encapsulation and routine monitoring is not enough to prevent damage. When damage occurs, removal may be the best option.