The hardest part of asbestos removal is making sure the particles stay out of the air. Different asbestos-containing materials (ACMs) are removed by different methods, but the one thing they have in common is to avoid filling the air with the kind of dust that's taken for granted in other demolition or renovation projects. The most general method that works well for asbestos is moisture. Though fibers do not dissolve in water, it does stick to them enough to make them settle quickly to the floor with the other components of their matrix.
Even though it sounds simple, doing it well enough to protect your family can be extremely complicated, especially when there is a large amount of highly friable asbestos-containing material to be removed. The costs of expert removal start at thousands of dollars for a small, easily accessed area like a floor with relatively nonfriable ACM. Everyone concerned with asbestos agrees that removal is the remedy of last resort, and the only preventative of later accidental exposure.
Removal of non-regulated asbestos-containing materials can be legally performed by homeowners, ordinary building contractors, or licensed asbestos abatement contractors. They all have to meet the same legal standards for protecting workers, the environment, and the family that will use the home after removal. These are mostly set out as the National Emissions Standards for Hazardous Air Pollutants (NESHAP) regulations (Refer to 40 CFR Part 61, Subpart M). The work also must comply with the Occupational Safety and Health Administration (OSHA) regulations delineated in 29 CFR 1926.1101. Of course those licensed asbestos-abatement contractors will be most familiar with the regulations, most experienced in meeting them, and most efficient in protecting you from liabilities and exposure to asbestos hazards.
A number of states require removal of asbestos-containing materials before any structure is demolished. Several require notification and documentation of the asbestos situation even if there is no asbestos before demolition begins. Surprisingly, there do not appear to be any requirements for alerting firefighters who may be called to attend to an emergency at a building with ACM. There has not been any study conducted firefighters' exposure to asbestos on the job or training of firefighters for dealing with ACM. While firefighters now almost always wear full breathing apparatus while inside an actively burning building, those working outside or on more minor fires may not, and "civilians" attracted to the emergency certainly will not. States' regulations about demolition of a building with ACMs do apply to intentional "training burns" of buildings by firefighters.
Any work area where large amounts of ACM are being disturbed should be isolated from the rest of the house by shutting down ventilation systems -sealing them, not just closing vents - and lining windows and doors with plastic sheeting and duct tape. Workers should never come out of that area into the rest of your home without stripping off all exposed clothing and discarding it with the other asbestos-containing waste.
To minimize the creation of dust, all asbestos-containing materials should be removed in as large pieces as possible. Experienced abatement contractors are familiar with this concern and plan carefully for it. During demolitions or renovations a contractor might choose to remove an entire boiler, a section of pipe, or other facility components without first removing the asbestos insulation that is on them. A large piece of debris, even if it is heavy and unwieldy, has fewer exposed surfaces that might release dust. This is especially true if the asbestos has already been encapsulated. Still, stripping operations are the most common form of asbestos removal during renovation.
Friable spray-on asbestos-containing material (which includes fireproofing materials found on decking and support I-beams) is normally easy to wet throughout because of the absorbency of the cellulose matrix. The material should be saturated all the way through and may require several rounds of spraying. Afterwards the substance can be simply scraped off. Other ACMs, such as "thermal-block" insulation used on pipes and boilers, certain ceiling and floor tile applications, and other materials that do not absorb water readily may be hard to penetrate. These materials will have to be wet down prior to, during, and in most cases, after removal to prevent the release of asbestos fibers. Whenever such materials are broken during removal, dry surfaces must be wetted immediately. A professional removal crew generally includes individuals assigned exclusively to keeping material wet from the time it falls to the time it's sealed in a bag for disposal. Other workers may have the job of keeping everyone else supplied with water. Adding detergent (one ounce to five gallons) help penetrate the water even better.
Obviously, keeping everything wet can be more of a hazard than the asbestos in some circumstances. The Asbestos NESHAP allows two exceptions to its wetting requirements: when the temperature falls below freezing, and when the presence of water endangers safe use of electrical or other equipment. Another universal method of minimizing the release of asbestos dust is to avoid using power tools.
Wetting agents are commonly applied with hand-pumped garden sprayers, or with hoses attached to a faucet tap, fire hydrant, or water tank. Professionals put a nozzle on the hose to turn the stream of water into a fine mist. In fact, after initial wetting of the ACM in a work area, a contractor may set up a misting unit to create generally high humidity within the isolated area to help capture any escaped fibers.
Cement asbestos board used for exterior siding or roofing may be removable with just a little care to avoid breaking it. It was probably predrilled for nailing, so it is most likely suspended from its original nails. You may be able to cut the heads off the nails and slip the pieces of asbestos-containing material off, or pull the nails clear out. The board is fairly hard and the asbestos fibers well embedded -and you are outside- so there is less risk of contamination than in an enclosed area. It is still important to protect yourself and keep others who are not part of the operation out.
What drives the decision to remove asbestos?
Removal is the remedy of last resort. It is the only way to certainly protect your home and family from later, accidental release of asbestos. Eventually, when your home is ultimately demolished, if not before, the asbestos-containing materials will have to be removed separately and dealt with. A state-licensed, independent asbestos inspector can help you evaluate the suspected ACMs in your home, assess the risks of removal, treatment, and repair. They can also see what happens to them, test your air for asbestos fibers that may already have been released, and can monitor the condition of your asbestos-containing home year by year.
Damaged asbestos-containing material can drive the decision to remove with the most urgency. Losing even a small section of a textured ceiling will require removing all of that, and may prompt a decision to remove other ACMs in the house while you are at it. Less-friable materials may be encapsulated, enclosed, or repaired, for the time being.
What are the first steps to remove asbestos?
The first thing to do is make sure that asbestos fibers do not get loose, and if they do get loose, to contain them in a controlled area. The simplest way to keep them from getting into the air is to keep the asbestos-containing material, even if it is only suspected, wet. If some material you suspect of containing asbestos has broken down and fallen, you need to isolate the room by closing and sealing vents, windows, and doors. This includes taping plastic over the slot below the door.
The next step is to verify that the material does contain asbestos, preferably by hiring a licensed asbestos inspector. The agency responsible for regulating asbestos in your state may be able to give you a list of licensed inspectors or you what to look for to verify their qualifications. The same agency should be able to help you find a trained and licensed contractor to actually remove the asbestos-containing material. Be sure to hire a contractor who is not connected with your asbestos inspector. The inspector will establish whether there is already asbestos in the air before removal begins, verify that the material does contain asbestos, and will verify that there's no asbestos left in the air after removal.
What are my liabilities in removing asbestos?
Federal regulations on removing asbestos are fairly general and mostly about protecting workers on the project from exposure to large numbers of fibers. Where things get specific is at state, county, and municipal levels, and the legal situation varies rather dramatically from one to another. It's not even easy to tell where to go for information. At the municipal level, it could be the health, building, or labor authorities, or some combination of agencies. The authorities in the fifty states, as identified by the EPA, include health, natural-resources, environmental, labor, and safety departments, and another full range of divisions and offices within those main agencies.
Remember, the property owner is liable for asbestos released into the air and people exposed on the property, on the way to disposal, or at the dump. Using a licensed contractor (and some jurisdictions require it) does not relieve you of that liability, but it makes it much less likely that there will be any damages for which to hold you liable. Experienced contractors know the regulations inside and out, probably have stockpiles of the forms that must be filed, and have the specialized equipment and training that have been developed to limit the release of asbestos and exposure of workers, neighbors, and your family.