During the first half of the twentieth century, asbestos cement was widely used for construction. In many respects, it was the ideal building material: strong, fireproof, and a good insulator. Untold numbers of homes, schools, office buildings, naval ships, and other structures were built with linings of asbestos.
After World War II (1939–45), scientists discovered that asbestos fibers can cause a variety of respiratory disorders in humans, such as lung cancer and asbestosis, a pneumonia-like condition. Discovering the relationship between asbestos and these conditions took a long time; the disorders commonly do not appear until 20 years or more after a person is exposed to asbestos.
Individuals most at risk for asbestos-related problems are those continually exposed to the mineral fibers. This includes those who work in asbestos mining and processing as well as those who use the product in some other manufacturing line, as in the production of brake linings. Over the past two decades, massive efforts have been made to remove asbestos-based materials from buildings where they are especially likely to pose health risks, as in school buildings and public auditoriums. Recent critics of asbestos removal maintain that—if not done properly—the removal process actually intensifies the problem by spreading more asbestos fibers into the air.
Read more:
http://www.scienceclarified.com/Al-As/Asbestos.html#ixzz3CztqLuUF
http://www.deir.qld.gov.au/asbestos/manage/wearing-ppe.htm
http://www.health.state.mn.us/divs/eh/asbestos/homeowner/ppe.html