Contrary to popular belief, the mere presence of asbestos in a structure is not enough to constitute a health hazard. Friable asbestos, which is asbestos that is easily broken down, is always a health hazard. Non-friable asbestos however, which is generally part of an indurated material that will not yield until under substantial effort. This means that human contact and weathering is unlikely to release the non-friable asbestos. Such is the lack of danger from non-friable asbestos, that experts generally recommend it remain within the structure, as disturbing it would only spread it in a friable state. Rather, non-friable asbestos is not likely to pose a danger through the inhalation of micro particles.
How can I tell if a material is non-friable?
Friable generally implies that you may break it apart with minimal effort with the use of your hands. Dried clay and chalk are good examples of friable materials. Friable materials will easily degrade into a fine dust, with or without pressure exerted on it.
A non-friable material will be:
– Difficult to crumble
– Will be unlikely to release fibers either due to its nature or being sealed in place
– Low risk of inhalation
The most important caveat here is that non-friable materials MAY become friable when damaged. This is important in demolition and home improvement as cutting, drilling or filing can potentially release asbestos where there were previously none.
What construction materials are considered non-friable?
All asbestos in construction material was eliminated in the late 1970s, but the government permitted material that had already been manufactured to be used in new home construction. Due to this rule, house built up to 1986 may have non-friable asbestos in them, or even dangerous friable material. All removal of asbestos must be done by a professional with special equipment.
Non-friable materials used in construction include:
Roofing products – shingles seal the asbestos with cement or other polymers to create a very efficient (for that time) insulator. These so called “asbestos roofs” are not dangerous until they are damaged. This can include acts of nature or remodeling. If the concrete or other sealant is broken, then the friable asbestos will be exposed, which is certainly a danger.
Roofing felt is also an asbestos containing product, typically 15 – 25% of it being asbestos. The rest is heavy paper and asphalt. This material was used to insulate commercial buildings and some houses and has copious amounts of white asbestos. As you can imagine, the heavy paper can be breached somewhat easily and the friable asbestos will be exposed here. Even if the roof tiles do not contain asbestos, the roof may be secured with asbestos felt, which poses the same risks.
Asbestos was used in roofing products due to its ability to fireproof and insulate. Safer alternatives have emerged since then. When removing these items, you need to have them checked for asbestos danger, as failure to do so will likely spread microfibers to you and your family.
Siding, which is material put on the sides of houses for insulation is subject to the same risks and precautions. Some siding consists of asbestos cement and remains safe until otherwise broken.
Weatherproofing – also known as base flashing, this is another insulator that was applied to roofs, skylights and vents to waterproof and insulate buildings. Tar paper, which was used as a barrier between the house and the shingles, also contains traces of asbestos. The EPA has since banned the use of asbestos based waterproofing.
Cement – asbestos cement is known as transite and has a number of uses throughout the 20th century. This includes concrete pipes, chimneys, ducts and fiber boards. Cement pipes that carry any number of waste, wiring, heating and water were lined with asbestos/cement mixture but this is not considered dangerous unless there is a rupture on construction done on the pipe. There is of course, the danger that the pipes carrying drinking water may erode and leech asbestos fibers into drinking water. All non-friable forms of asbestos are harmless until they are breached due to wear or force.
Furnaces –non-friable asbestos cement was used to coat, join and seal devices subject to extreme heat, including furnaces, stoves, boilers and areas in refineries and factories. As it is sealed in cement, there is no danger until the unit is compromised or demolished.
Vinyl Products – vinyl was popular in the American home during the 20th century and many applications contain non-friable asbestos. Like the other applications, the durability and insulation qualities of asbestos made it ideal for flooring and wall papering. For vinyl flooring, the asbestos is locked in until it is otherwise disturbed. The wallpaper benefitted from easy instillation and had the added benefit of being fire resistant. Both are not in sure anymore, but older homes may still have these services.
Demolition and non-friable materials
As mentioned, non-friable materials carry little risk as long as they were applied properly and remain intact. When demolishing a structure that contains non-friable materials, know that all materials must be removed and abated before a typical demolition can begin. Recall that friable material breaks easily in one’s hands. Demolition would be equivalent to that for non-friable materials, so the simple act of knocking down a building can become a health hazard if proper measures are not taken.
What are regulations on non-friable materials?
The EPA recognized two categories of non-friable materials. Category I refers to items that are not likely to become friable due to strong bonds or construction. Category II refers to items that are not weatherproof or cannot withstand impacts or frequent use.
Further rules about asbestos classify “regulated asbestos-containing material” as
– All friable asbestos material
– All weathered and damaged Category I products
– All Category II products likely to be become friable
RCMs are subject to strict federal regulation on exposure to workers, abatement and presence in certain protected areas.