Have you ever wondered how asbestos is safely removed from a property? Asbestos abatement also known as asbestos removal is an intensive process. To be clear, Indoor Science does not offer asbestos abatement or have financial ties with abatement companies. Earlier in my career, I worked as a project manager overseeing asbestos abatement at schools and commercial properties. While there are various ways to remove asbestos-containing materials, this blog will cover the most common abatement methods.
One of the largest parts of abatement is to partition off the work area, which is called “containment”. This process can range depending on the type and scale of abatement. A typical containment will contain decontamination chambers at the entrance which consist of an airlock and/or multi-chamber decon units with a shower and tool area. The bulk of the containment is made of thick plastic sheeting which can be built up like a tent. All HVAC registers and supplies are sealed off with plastic and along with doors and windows. To make sure there is no leakage from the containment, a negative air machine is installed in the containment which draws air in from the containment and exhausts it outside while being HEPA filtered. The negative pressure draws air into the containment from the surroundings which prevents the asbestos-laden air from escaping.
Floor Tile & Mastic Removal
Asbestos tile is one of the most commonly abated materials at properties either due to aesthetic renovation or degradation of the material. Vinyl tile removal is typically done in two ways. Either by heat removal or by gross removal. Heat removal involves heating the tile to the point where the tile separates from the adhesive substrate, thus removing it in a non-friable condition. The second option is gross removal which involves the physical removal by a variety of means which may render the tile friable– although is much faster than heat removal. Once the tile is removed, next comes with the removal of the adhesive (also known as mastic). Mastic removal usually involves placing a solvent on the mastic, but can also be achieved via gross removal methods. The mastic-removing solvents can pose an entirely different indoor air quality problem.
Pipe Insulation Removal
Pipe insulation removal can also be done using gross removal or the glove bag method. The glove bag method involves placing a plastic enclosure called a “glove bag” over a length of pipe insulation and sealing the ends. This creates a micro containment where an abatement worker can remove the pipe insulation within the bag while also having a water inlet to spray the pipe insulation down. The glove bag method and the heat removal both greatly reduce fiber release, but are more time consuming than gross removal.
Surfacing Material & Wall System Removal
Surfacing material and wall system removal will usually be conducted via gross removal. Since these are friable materials, the abatement will require substantial amounts of amended water (water with a surfactant such as soap) to minimize the fiber release. Removal of surfacing materials like popcorn ceiling will require scraping, while plaster can be taken down with more mechanical means.
Disposal, Cleaning, & Clearance
Once the materials are removed, they are double-bagged and will be disposed of in a proper landfill equipped for asbestos waste. The containment is thoroughly cleaned by HEPA vacuuming and wet wiping the area with amended water. Once this is complete, a third-party air sampler will inspect the containment to verify if the material has been removed and conduct air sampling. Once the air sampling results show that the containment has met clearance criteria, the containment can be disassembled.
Because of the many important steps, the State of Illinois requires that anyone offering this service be a licensed asbestos contractor.