Although fiberglass was thought to be a "safe" substitute for asbestos, researchers later found that it too was associated with the risk of lung cancer and lung disease. Fiberglass is one of a group of products known as man-made mineral fibers or man-made vitreous fibers. They are generally divided into three groups: Fibrous glass, mineral wool (i.e., slag wool and rock wool), and ceramic fibers.
There is the potential for fiberglass exposure from ceiling insulation if it is in a state of disrepair. Fiberglass insulation that is falling off the ceiling may be a hazard if there is enough air movement to displace the fibers from the insulation material. Air borne fibers can land on workers in the area or they can accumulate on work areas, tools, and floors. Dry sweeping of accumulated fibers could make them airborne near the worker's breathing zone. Fiberglass dust should be removed using wet cleaning methods.
Glass fibers can produce skin irritation, intense itching, and even contact dermatitis. Some workers also experience respiratory tract irritation.
OSHA treats fiberglass as a nuisance dust and has set the permissible exposure limit at 5.0 mg/m3 for respirable dust and 15.0 mg/m3. Manufacturers have been recommending an exposure limit of 1 fiber/cm3.
Until this hazard has been abated, there are some precautions workers should take. For example, using long-sleeved shirts, coveralls, and other clothing will help prevent irritation by keeping fibers off the skin. Washing or showering at the end of the day will also help.