Asbestos abatement
Encyclopedia
Asbestos
Asbestos is a set of six naturally occurring silicate minerals used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long, thin fibrous crystals...
, which was used in spray-applied flame retardant
Flame retardant
Flame retardants are chemicals used in thermoplastics, thermosets, textiles and coatings that inhibit or resist the spread of fire. These can be separated into several different classes of chemicals:...
, thermal system insulation, and in a variety of other materials. Asbestos was sometimes "flocked
Flocking (texture)
Flocking is the process of depositing many small fiber particles onto a surface. It can also refer to the texture produced by the process, or to any material used primarily for its flocked surface. Flocking of an article can be performed for the purpose of increasing its value in terms of the...
" above false ceilings, inside technical ducts, and in many other small spaces where firefighters would have difficulty gaining access. Structural components like asbestos panels were also used. In residences, asbestos was often a component of a type of flocked acoustic ceiling called "popcorn ceiling" or "cottage cheese ceiling", until its production was banned in the U.S. in 1978. However, the ban allowed installers to use up remaining stocks, so houses built as late as 1986 could still have asbestos in their acoustic ceilings. The only way to be sure is to remove a sample and have it tested by a competent laboratory.
Rationale
Depending on how and where asbestos was applied, it might not pose any risk to most users of the building. If the fibers cannot become dislodged, they cannot be inhaled, and thus the asbestos poses no risk.However, some methods of applying asbestos, particularly flocking
Flocking (texture)
Flocking is the process of depositing many small fiber particles onto a surface. It can also refer to the texture produced by the process, or to any material used primarily for its flocked surface. Flocking of an article can be performed for the purpose of increasing its value in terms of the...
, allow asbestos fibers to gradually drop off into the air. Asbestos poses hazards to maintenance personnel who have to drill holes in walls for installation of cables or pipes.
Even if the workers are protected, such maintenance operation may release fibers into the air, which may be inhaled by others. Interventions in areas where asbestos is present often have to follow stringent procedures.
When asbestos fibers can easily be made into airborne dust, the material is known as friable. For example, a "popcorn ceiling" is extremely friable, whereas asbestos floor tile is considered non-friable.
Removal procedures
If removal is to be performed when users are still present in the building, it is usually necessary to relocate some users temporarily. Typically, the part of the building from which asbestos is being removed has to be sealed off in order to prevent contamination of the other areas. Methods of sealing off an area often include the use of PolyethylenePolyethylene
Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...
film, duct tape
Duct tape
Duct tape, or duck tape, is cloth- or scrim-backed pressure sensitive tape often sealed with polyethylene. It is very similar to gaffer tape but differs in that gaffer tape was designed to be cleanly removed, while duct tape was not. It has a standard width of and is generally silver or black...
and negative air pressure machines which are fitted with HEPA
HEPA
High-Efficiency Particulate Air or HEPA is a type of air filter. Filters that are awarded the HEPA accolade are used in various locations, whether in medical facilities, automotive vehicles, airplanes, home filters, or wherever very pure air is sought. The filter must satisfy certain standards of...
filters. The idea is that the contained area is pulling fresh air in as to not allow asbestos fibers into the surrounding environment.
Only a special vacuum cleaner that's designed for asbestos containment (class H) can be safely used when cleaning up during and after asbestos removal. Ordinary vacuum cleaners cannot be used, even those fitted with a HEPA filter. An ordinary vacuum cleaner will expel the asbestos fibres into the room air.
If the building is closed to normal users, it may be necessary to seal it off from outside atmosphere so that no accessible air is contaminated. Examples of asbestos removal enterprises include the Jussieu Campus
Jussieu Campus
The Jussieu Campus is a higher education campus located in the 5th arrondissement of Paris, France, which is the main campus of the Pierre and Marie Curie University ....
(begun circa 1996 and still going on ) and the Tour Montparnasse
Tour Montparnasse
Tour Maine-Montparnasse , also commonly named Tour Montparnasse, is a tall office skyscraper located in Paris, France, in the area of Montparnasse. Constructed from 1969 to 1972, it was the tallest skyscraper in France until 2011, when it was surpassed in height by the Tour First...
(in 2005, projected duration was three years if the tower was emptied of its users, and ten years if it were not).
Removal is not the only means of asbestos abatement. Asbestos and asbestos-bearing materials may be "enclosed" or "encapsulated" to prevent building occupants from being exposed to the fibers.
An asbestos-containing building that is to be torn down may have to be sealed (see third picture on right), and to have its asbestos safely removed before ordinary demolition
Demolition
Demolition is the tearing-down of buildings and other structures, the opposite of construction. Demolition contrasts with deconstruction, which involves taking a building apart while carefully preserving valuable elements for re-use....
can be performed. The asbestos removal may take longer and cost more than the actual demolition. For example, the former seat of parliament of East Germany, the Palast der Republik
Palast der Republik
The Palace of the Republic in Berlin was the seat of the parliament of the German Democratic Republic, the People's Chamber, and also served various cultural purposes...
, was stripped of most of its asbestos between 1998 and 2001, before it was finally demolished starting in 2006.
See also
- AsbestosAsbestosAsbestos is a set of six naturally occurring silicate minerals used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long, thin fibrous crystals...
- MesotheliomaMesotheliomaMesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...
- AsbestosisAsbestosisAsbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...
- AsbestineAsbestineAsbestine is a mineral compound composed of nearly pure fibrous magnesium silicate, with physical characteristics between those of asbestos and talc. It is used in paper manufacture and construction.-Applications:...
- Asbestos and the lawAsbestos and the lawThis article concerns asbestos-related legal and regulatory issues. Litigation related to asbestos injuries and property damages has been claimed to be the longest-running mass tort in U.S. history...
- FibroFibroFibro, the shortened form of "Fibrous Cement" - or "Fibrous Asbestos Cement", FAC, is a building material made of compressed fibres cemented into rigid sheets....
- FireproofingFireproofingFireproofing, a passive fire protection measure, refers to the act of making materials or structures more resistant to fire, or to those materials themselves, or the act of applying such materials. Applying a certification listed fireproofing system to certain structures allows these to have a...
- List of minerals
- VermiculiteVermiculiteVermiculite is a natural mineral that expands with the application of heat. The expansion process is called exfoliation and it is routinely accomplished in purpose-designed commercial furnaces. Vermiculite is formed by weathering or hydrothermal alteration of biotite or phlogopite...
- Wittenoom, former asbestos mining townWittenoom, Western AustraliaWittenoom is a ghost town located 1,106 kilometres north-northeast of Perth in the Hamersley Range in the Pilbara region of Western Australia. It is the site of Australia's greatest industrial disaster....
- Asbestos Project Monitor
External links
- Fibrous Asbestos Cement sheeting Removal procedures etc.A personal view from a retired licensed removalist. (Australia)
- Asbestos Abatement & Testing Resources