Asbestos is Hazardous When Damaged, Crumbled or in Need of Repair
Asbestos was used in almost every public and commercial building constructed before the 1980's in the United States. As a fireproofing material, it was applied on steel beams and columns during construction of multistory buildings. Because of its strength, asbestos was added to concrete, asphalt, vinyl materials in roof shingles, pipes, siding, wall board, floor tiles, joint compounds and adhesives. Its heat-resistant qualities made asbestos the perfect thermal insulation. The material was also used in acoustical plaster and as a component of a mixture sprayed on ceilings and walls. In short, it was the miracle material of the building industry.
However, asbestos becomes a hazard when it is damaged, crumbles, or is in a state of disrepair. It then poses a health risk to building occupants, repairmen, and maintenance workers because asbestos fibers may be released into the air. The risk is even greater if the building is demolished, renovated, or remodeled.
Because of the serious problems associated with asbestos exposure, the Environmental Protection Agency (EPA) emphasizes that asbestos in buildings should be located and appropriately managed, and requires that workers who disturb asbestos be specially trained (Asbestos Informer, EPA). In some cases, asbestos-containing material may be contained by using encapsulants, which are materials applied in liquid form to provide a seal against the release of asbestos fibers. In other cases, such as when the asbestos is widespread and friable (easily crumbled or reduced to powder) or likely to become friable, removal of the asbestos is the only acceptable course of action.
The National Emission Standards for Hazardous Air Pollution Act (NESHAP), 40 CFR Part 61, Subpart M, applies to potential public exposure to asbestos in public, commercial, and some residential buildings that are being demolished or renovated. These buildings must be inspected by a licensed asbestos inspector to determine the presence or absence of asbestos. NESHAP contains detailed descriptions of what asbestos materials are friable, what materials are likely to become friable, and under what conditions non-friable asbestos becomes dangerous such as through sanding, grinding, and cutting (Asbestos/NESHAP Regulated Asbestos Guide, EPA). The Act also prohibits the use of spray asbestos, and of wet applied and molded insulation (pipe lagging) containing asbestos.
Building owners and those in charge of asbestos removal must notify state and local agencies and EPA offices before demolition or renovation activity begins. NESHAP asbestos removal requirements include sealing off the area from which the asbestos will be removed; shutting off forced-air heating systems, fitting asbestos workers with approved respirators and other protective gear, wetting asbestos during the removal process, specialized cleaning of the area after asbestos is removed, and containing and labeling asbestos waste for appropriate disposal at an approved landfill.
The Occupational Safety and Health Commission (OSHA) also regulates work procedures for asbestos removal, including requiring the use of enclosures, ventilation systems, and certain filters. See Worker Safety for details.