Asbestos is the name for a group of naturally occurring minerals that possess very unique properties. These mined minerals have the ability to be continuously separate into strong, very thin, microscopic fibers. These fibers are extremely durable along with being highly resistant to temperatures and caustic chemicals. The unique properties of asbestos along with it being inexpensive and readily available made it very attractive to manufacturers during the last century. This usefulness resulted in asbestos being used in hundreds if not thousands of different product used in and around homes, factories, schools and public buildings. Just about any building constructed the last century up to the mid 1980’s must be looked upon as possibly containing asbestos materials. When asbestos is found and positively identified it may or may not pose a health hazard to building occupants. The level of hazard depends upon its condition and the risk with its potential to be released into the surrounding environment. When asbestos can be crushed by hand pressure or released to the air by knocking it or brushing up against it then the material is considered FRIABLE. Asbestos should never be allowed to reach a condition of being friable and building owners need to take on the responsibility of making sure this is the always the case. Friable asbestos poses a threat to all those that enter the surrounding location and can pose a significant health risk. However, as long as the surface of asbestos is stable and well-sealed against the release of its fibers the material is considered safe until damaged in some way.
When asbestos is abraded it tends to break down into microscopic size fibers. Because of their size and shape, these tiny fibers remain suspended in the air for long periods of time and can easily penetrate conventional filtration systems. If these fibers are inhaled or ingested because of their small size they can make their way into parts of our bodies that normal dust particles never reach. This is what makes asbestos different and this is why we have laws that require certain procedures be taken to prevent these fibers from entering our systems. When these fibers are within our bodies certain diseases that have latency periods of 10 to 30 years after exposure can become prevalent. Asbestosis and Mesothelioma are two such diseases that asbestos exposure can contribute to. What level of exposure that directly causes these diseases is not a know science. Therefore, avoiding exposure to friable asbestos should be avoided whenever possible. When planning renovations or demolition projects you must be aware that many of the materials you will be disturbing and disposing of have the potential to contain asbestos. Materials such as floor tiles, linoleum sheeting, pipe insulation, boiler insulation, mastic adhesives, joint compounds, window glazing, roofs, duct insulation, siding, sprayed on or rolled on textured ceilings and many other items should be tested or visually confirmed as to whether of not they contain asbestos before they are touched. If the material needs to be removed in order to complete your project keep in mind that most home repair or remodeling contractors do not have certification or certified workers nor are they equipped to work with asbestos safely. If you hire someone who is not a Licensed asbestos professional to handle asbestos issues not only have you potentially subjected yourself and your family to serious health dangers, but also there can be legal problems because of local, state, or federal laws regarding environmental protection and workers’ health.
If the contractors do not have the right equipment and expertise to perform the work improperly they could spread asbestos fibers throughout your home and into the surrounding neighborhood. They may create an asbestos hazard where none existed or make an existing friable situation worse.
Remember, as the owner of the property, you are responsible for the safe disposal at an EPA approved landfill, even if you have hired someone to do the work for you.
IF YOU THINK ASBESTOS HAS BEEN RELEASED IN YOUR HOME,
WHAT SHOULD YOU DO?
If the release appears significant (for example, 4 or 5 square feet of sprayed-on ceiling material or 1 to 2 feet of pipe insulation) close off the portion of the house, such as a bedroom or the basement in which the problem has occurred so that people will not be exposed. Close off air ducts and vents, shut windows, and tape bottoms of doors to prevent drafts. Contact a licensed asbestos professional as soon as possible.
You will probably want to have samples of dust or debris from floors, shelves or window sills taken and analyzed by a laboratory licensed to analyze asbestos fibers. Air samples may also be needed to define the situation; if so, once again, they must be taken and analyzed by a laboratory that has the proper training and equipment.
Analysis of material (bulk samples) and air samples will provide the information needed to decide what further measures may be required.
WHEN YOU MAKE MAJOR CHANGES IN YOUR HOME
Depending upon the amount of asbestos-containing material present, you may be required to notify authorities in your area before you remodel, dismantle, or demolish your home or part of it. They will want to know what work is intended and your proposed method of asbestos removal and disposal. The law also requires that “no visible emissions” of dust are allowed during removal, transportation, and disposal of asbestos-containing materials.
COMMON LOCATIONS OF ASBESTOS MATERIALS
FURNACES, BOILERS, HEATERS, & PIPING
Insulation blankets (the outside covering or shell), inside metal exterior jackets,door gaskets, duct insulation, combustion chambers and tape at duct connections of furnaces and boilers all may contain asbestos. It was used as the “best material available” during its time as a high-temperature insulation. Oil, coal, gas or wood furnaces with asbestos-containing insulation and cement are generally found in older homes with its installation dating between 1900 and 1980. If you furnace was installed during this time period then the likelihood of their being asbestos on the exterior or interior is very high.
Steam and hot water pipes were insulated with asbestos-containing material, particularly at elbows, tees, and valves. Its appearance is similar to that found on boilers. This insulation was mixed with water at the site and applied over the surface to be covered. Typically this insulation can be very difficult to remove and gives the most difficulty when being removed. Most Pipes may also be wrapped in an asbestos “Air Cell” , Solid “Magnesia” or asbestos paper. Asbestos-containing insulation has also been used on and inside round and rectangular furnace ducts. Sometimes even the duct itself may be made of asbestos-containing materials.
Exterior walls and closed decks were sometimes built with a fire retardant sheeting in the form of asbestos paper. If it looks like a thick gray cardboard, it may contain asbestos. If left undisturbed and in good condition, the under-sheeting is considered safe. However, if you are taking out a wall for expansion and remodeling, or if you are replacing siding and shingles, you could release many fibers in the process of drilling, sawing, and removing.
Cement asbestos board (commonly referred to as CAB) has been used in houses as sheets for straight and lap siding and has been cut and shaped as a substitute for wood shingles for roofs and exterior walls. The material is hard and brittle, normally light gray in color, was pre-drilled for fastening, and often was factory primed and painted. Since this material is mainly outside the home, and the asbestos is bound in a hard material, it presents little hazard, unless altered by drilling, sawing, or sanding. When CAB becomes worn or damaged, spray paint it to ensure sealing in the fibers.
INSULATION: WALL & CEILING
Loose blown-in mineral wool and batt insulation infrequently have been known to contain asbestos. However there is now the concern about Vermiculite insulation possibly containing asbestos fibers. Please refer to this link to answer questions about vermiculite http://www.epa.gov/asbestos/pubs/verm.html
Having a full, professional answer to the vermiculite question is very difficult due to the “gray area” presented by regulatory authorities. At this time the approach to answering this topic falls of personal preference and learning the facts prior to dealing with vermiculite is the best advice we can give. The areas where vermiculite is found include outside walls and floor or roof/attic spaces between structural joists and rafters.
Joint compound installed from the 1940’s to the 1970’s has the potential to contain asbestos.
Sheet vinyl (including the backing or under-layment), vinyl tile, and vinyl adhesive may all contain asbestos. In these products asbestos fibers were added as a matrix to the basic materials to give them strength and durability. These products are considered safe unless the flooring is altered or damaged. Damage could occur as a result of prolonged or excessive abrasion, breaking, sawing, cutting, grinding and sanding. This damage can thus release asbestos fibers into the environment. When replacement or repair becomes necessary, these flooring products need to be handled by an asbestos professional and disposed of in an EPA approved landfill that accepts asbestos waste.
INTERIOR SURFACES: WALLS AND CEILINGS
Sprayed-on or toweled-on surface material on wall and ceiling surfaces of some homes may be composed of asbestos-containing materials. If the surface material is firmly attached, has a hard surface, and has no water damage, it should not be hazardous. If the surface can produce powder or dust by hand pressure, it is advisable to seek professional advice before deciding what further course of action to take.
Materials in older lamp socket collars, electric switch and receptacle boxes, liners for recessed lighting, backing for switchboard panels, fuse boxes, and old-fashioned “knob & tube” wiring have all, at times, been found to contain asbestos. Normal use of these items should not pose a hazard. Replacement products in these categories do not contain asbestos. We can dispose of these items, when they are replaced, in an approved manner.
Oven & dishwasher (in cabinet) units were often wrapped in asbestos-containing insulation blankets or sheets until the mid-1970s.
Older gas-fired decorative fireplace logs and artificial ashes may have a considerable amount of asbestos fibers and, if disposed of, should be handled in the same manner as other asbestos materials.