Asbestos is a wonderful product that served many purposes for years because it is fibrous material that acted as a stabilizer in many products and because it was fireproof it was a great insulator. Its usage was banned in specific applications in 1980 because the fibers, if breathed can ultimately cause asbestosis or mesythelioma both of which are fatal lung diseases. It is believed that just a single fiber is enough to cause disease. It is still used today but only very limitedly.

In older housing we still find asbestos in many places including but not limited to:

cementitious siding

roof cement

plaster

floor tile

texturing on ceilings

insulation in attics and around pipes

the expansion boot in furnace plenums

joint compound

This list is by no means complete but only meant to show how pervasive asbestos was. The whole key to asbestos is keeping it out of the air. If you suspect asbestos do not try to remove it yourself. If the fibers are released into the air they can stay there for a very, very long time. Asbestos removal is NOT do-it-yourself job. It is best to  call in a professional.