shredded, or scuffed). When found in the home, asbestos often resembles grayish-white corrugated cardboard coated with cloth or canvas, usually held in place around pipes and ducts with metal straps. Things that typically might contain asbestos: Boiler and furnace insulation. Heating duct wrapping. Pipe insulation ("lagging"). Ducting and transite pipes within slabs. Acoustic ceilings. Textured materials. Resilient flooring. Blown-in insulation. Roofing materials and felts. Health and safety issues Spray polyurethane foam (SPF) All polyurethane foams are composed of petrochemicals. Foam insulation often uses hazardous chemicals with high human toxicity, such as isocyanates, benzene and toluene. The foaming agents no longer use ozone-depleting substances. Personal Protective Equipment is required for all people in the area being sprayed to eliminate exposure to isocyanates which constitute about 50% of the foam raw material. Fiberglass Fiberglass is the most common residential insulating material, and is usually applied as batts of insulation, pressed between studs. Health and safety issues include potential cancer risk from exposure to glass fibers, formaldehyde off-gassing from the backing/resin, use of petrochemicals in the resin, and the environmental health aspects of the production process. Green building practices shun Fiberglass insulation. The World Health Organization has declared fiber glass insulation as potentially carcinogenic (WHO, 1998). In October 2001, an international expert review by the International Agency for Research on Cancer (IARC) re-evaluated the 1988 IARC assessment of glass fibers and removed glass wools from its list of possible carcinogens by downgrading the classification of these fibers from Group 2B (possible carcinogen) to Group 3 (not classifiable as to carcinogenicity in humans). All fiber glass wools that are commonly used for thermal and acoustical insulation are included in this classification. IARC noted specifically: "Epidemiologic studies published during the 15 years since the previous IARC Monographs review of these fibers in 1988 provide no evidence of increased risks of lung cancer or mesothelioma (cancer of the lining of the body cavities) from occupational exposures during manufacture of these materials, and inadequate evidence overall of any cancer risk." The IARC downgrade is consistent with the conclusion reached by the US National Academy of Sciences, which in 2000 found "no significant association between fiber exposure and lung cancer or nonmalignant respiratory disease in the MVF [man-made vitreous fiber] manufacturing environment." However, manufacturers continue to provide cancer risk warning labels on their products, apparently as indeminfication against claims. However, the literature should be considered carefully before determining