Using asbestos in buildings was quite common before its health risks were fully realized. At one time, asbestos was regularly sprayed onto steel beams as a fire retardant. It was also wrapped around pipes as insulation and sprayed onto ceilings as a fire retardant. Asbestos was also used in numerous floor and ceiling tiles prior to 1980.
Asbestos is most dangerous when it can be inhaled, or to a lesser extent, ingested. If it can be crumbled and form airborne particles, it is “friable,” and poses a serious health risk.
Today, asbestos is still present in many buildings. Workers performing new construction will not be asked to use asbestos that can become friable. But, workers performing HVAC repair or replacement, plumbing repair or replacement, or renovation work, are likely to come across old asbestos.
Before doing any of these tasks in older buildings, it is important for a trained person to identify asbestos and make sure that, if it is to be disturbed, the work is done safely.
Containment must be used in all cases where asbestos will be removed or may become damaged. The extent of containment depends on the size of the job. For total removal projects, trained asbestos contractors should perform the task before any other work takes place. For smaller jobs, properly trained and equipped workers can remove asbestos safely, again as a first step, before other work.
Removal jobs all share four main features:
- Containment – Usually plastic barriers are put in place to prevent asbestos from getting spread around the work area. These can range from glovebags around small sections of pipe to multi-room containment areas with negative air flow, showers, and change rooms.
- Wetting – A surfactant (wetting agent) and water are gently sprayed onto asbestos to keep it moist, so it does not become airborne.
- Personal protective equipment – Workers need to wear at least a properly fitted airtight half-face respirator with high efficiency particulate air (HEPA) filters and impervious gloves. Greater protection is needed for bigger jobs, such as a full-face or positive air respirator and impervious full-body suits.
- Disposal – Must be double bagged, properly marked, and disposed of as hazardous waste.
Safe Building Maintenance
It is not necessary to remove undamaged asbestos from buildings. Undamaged asbestos can be encapsulated or enclosed to keep it from becoming airborne.
Encapsulation is usually used on pipes and is sprayed to create a barrier of protection directly on the asbestos surface.
Enclosures are containers surrounding asbestos, usually a vertical beam or pipe that are air tight. Removal and repair, as well as encapsulation and enclosure, are all considered activities that have the potential to release friable asbestos into the air. Safety precautions must be used for all of these activities.
Construction can be dangerous work. Asbestos can make it more dangerous. Be sure to use proper precautions before handling asbestos.