Asbestos is a term for a group of naturally occurring minerals. These minerals are unique in that their molecular structure is fibrous in nature. This particular quality made asbestos minerals attractive to add to literally hundreds of building materials (pipe insulation, shingles, roofing products, fireproofing, acoustical treatments etc.). Asbestos was also used in many different types of flooring products (all 9"x9" tiles, some 12"x12" tiles, and mastics used to glue the tile to the flooring substrate).
Hazards of Asbestos
Asbestos is a respiratory hazard and respiratory/gastro intestinal carcinogen. Exposure to asbestos occurs when respirable fibers are released into the air and then inhaled. Since exposure occurs when asbestos is inhaled, the best way to prevent exposure is to prevent asbestos fibers from becoming airborne.
Asbestos containing materials are therefore divided into two categories: friable and non-friable. Friable means that a material is able to be reduced to a powder by hand pressure. Asbestos containing materials that are friable, by their nature, have a much greater tendency to release fibers into the air. Conversely, non-friable asbestos containing materials, by their nature, do not want to give up their fibers into the air. This class of materials must be mechanically impacted (power tools such as sanders, drills, chippers, saws, etc.) to release fibers. Asbestos containing flooring and mastics are classified as non-friable materials.
There are several levels of protection to help prevent asbestos fiber release during asbestos flooring/mastic removal projects.
- Flooring/Mastics are Non-friable – As mentioned above, floor tile and mastics are non-friable materials and as such do not want to readily release their fibers. The cohesive matrix of the materials binds the fibers together with other materials. A great deal of energy is required to separate the asbestos fibers and release it in a respirable form.
- No Power Tools used for Removal – The contractor is required (by the University's specifications and OSHA and EPA regulations) to use non-abrasive, non-power tool removal techniques. In simple terms, they can only use hand tools (scrapers, chisels, shovels, etc.) to remove the flooring and mastic from the concrete deck of the building. A chemical is used to clean off any mastic that remains on the concrete after scraping.
- Wet Methods – Whenever asbestos containing materials are disturbed in any manner, the material must be wet. Materials that are wet do not release respirable particles into the air.
- Waste Material Handling – Once materials are removed, they must be double wrapped in layers of 6 mil thick plastic and then sealed with duct tape. The materials also must be segregated into a dumpster used only for asbestos waste. No removed asbestos containing materials are permitted to accumulate in the building or on the job site.
- Trained & Certified Workers – In accordance with the University's specifications and County, State and Federal regulations, the workers removing the flooring materials are trained and certified in accordance with an EPA recognized training program. The contractor is certified and registered for this type of asbestos work as well.
Some Other Information
You may see some of the contractor's employees putting on respirators and white suits. This can be, quite understandably, a little disturbing. However, OSHA regulations require that all persons working with asbestos containing materials wear respiratory and other personal protective equipment while they are working, regardless of other control methods in place the prevent the release of fibers. Signs at the entrance to work areas are also an OSHA requirement to inform people of the area where asbestos containing materials are being removed.