Asbestos and Fires
For over a century asbestos has been used extensively throughout the world as an insulating compound and fire retardant. Asbestos is a natural mineral compound that is composed of tiny fibers, easily mined and processed into tiles, wall panels, pipe wraps and is even mixed with cement to provide a fire barrier. Unfortunately it is the asbestos fibers themselves which pose the greatest threat to human health, and the use of this material as a fireproofing agent often results in inhalation of asbestos by people, especially during and after a fire. Lung cancers such as mesothelioma are directly related to asbestos.
Asbestos in Buildings
Older buildings often have asbestos installed in them as a means to protect workers from high heat, and this is especially the case in power plants, metal works, shipyards, foundries and other structures containing furnaces and boiler rooms. Many of these buildings are abandoned and sit unoccupied; they are a prime target for danger by fire because there is no one in attendance to signal an alarm or put out the blaze. During extremely dry periods brush fires are common, and if the prevailing winds carry ash or flame to an aging structure containing asbestos, the structure may burn, with the asbestos protecting only certain vital parts of the interior.
In the end, the asbestos will be one of the only substances remaining after the fire, but because it was built into the walls of the structure or used as a covering on electrical panels, the fibers will become loosened in the high heat. Since they are fire-resistant, the fibers will become airborne and travel away from the building remnants, carried by the prevailing winds and the heat convection from the flames. The asbestos can then settle in a new location and the danger from these loose fibers can be quite serious.
During a fire, the responding firefighters often wear a protective breathing apparatus to keep them safe from inhaled soot and gases. However these are often not worn after a fire is extinguished, and the free-floating asbestos that has escaped the weighting effects of water or other repellant are now a danger to the firefighters themselves. In the last two decades a number of safety measures have been put into operation to deal with the possibility of asbestos exposure after a building fire, and these procedures include keeping the area wet until all possible residues has been removed from the structure. An undergoing assessment of older buildings containing asbestos reveals that there are still a great number of structures where asbestos has yet to be removed; the installation of this material has all but ceased in the U.S. and many other countries. However this data compilation on asbestos remains incomplete, so firefighters and neighboring business, homes and schools are still at risk from fires in structures containing this material. References: