If you have an interest in demolition – either as a worker or spectator – you need to keep in mind that demolishing older structures may put you at risk of asbestos exposure. This is why there are strict federal laws dictating how asbestos must be handled both before and during demolition projects.
Where in an old building can you find asbestos?
During much of the 20th century, asbestos was a popular component of construction materials because of its strength, ability to resist fire and capacity to insulate against heat and sound. However, during the 1970s, responsible companies began eliminating asbestos from their manufacturing processes because of the link between exposure to the mineral and the development of fatal diseases, such as malignant mesothelioma.
In fact, the Environmental Working Group estimates that every year, asbestos-related diseases claim the lives of more than 9,900 individuals in the U.S. This underscores the importance of protecting both consumers and industrial workers from asbestos exposure.
As listed by the federal Environmental Protection Agency, items in and around buildings that may contain asbestos include, but are not limited to:
- Cement corrugated sheets
- Cement flat sheets
- Cement shingles
- Cement pipe
- Pipeline wrap
- Roofing felt
- Roof coatings
- Non-roof coatings
- Vinyl floor felt
How should asbestos be dealt with before demolition?
When a building is torn down, there is a lot of potential for dangerous substances to be released into the environment, putting the health of both workers and local residents at risk. That’s why the federal government has strict laws dictating the handling of asbestos before a demolition project commences.
First, the National Emission Standards for Hazardous Air Pollutants, or NESHAP, requires that any building manager or operator notify the appropriate state agencies before demolition takes place. Next, demolition workers have to be careful about controlling the emissions of potentially deadly substances.
When it comes to asbestos, that means minding both friable – that is, it can crumble when handled – and non-friable asbestos products that may become damaged during the demolition must be removed prior to the actual demolition.
If the removal process is likely to disturb any of these materials, those in charge of the project have to make sure they’re kept adequately wet in order to control the dust problem.
Similarly, anything that cannot be physically removed from the site before demolition must be kept wet until its actual disposal after demolition. The goal here is to make sure that there is no visible dust.
There are only two exceptions to the rule regarding keeping these materials wet prior to demolition:
- If the temperature at the time of wetting is below zero. Building owners and operators must make a note of these temperatures and keep the records for at least two years.
- When the use of water will damage equipment or present a safety hazard. This requires written approval from safety inspection administrators.
Building owners and operators have to keep in mind that inspectors will also be on hand to make sure that the wetting procedures are being carried out properly. They can evaluate things such as the location of the water supply, whether an alternative wetting agent is needed, what equipment is being used to wet the materials and how properly bags of waste are handled.
If those in charge of a demolition project know that air concentrations of asbestos fibers may exceed permissible exposure limits, they must provide workers with protective clothing and respirators.