The hazard of airborne asbestos fibers depends to a great extent on the condition of the material, how often people go into the room where it’s located, and how much air moves through the space.

It’s when asbestos is friable—flaking or crumbling—that it’s likely to become airborne. Both the EPA and the Consumer Product Safety Commission recommend leaving asbestos alone unless it’s friable.

Asbestos materials in good shape often can be “encapsulated” by an asbestos abatement contractor to add a layer of protection. This involves coating asbestos with a heat-resistant paint or sealant (approved by the EPA) that creates a protective barrier and converts surface fibers into a safer form.

Be advised that encapsulating asbestos may be temporary and almost as expensive as removal, depending on the project, and may make later removal more difficult.

Pipes or ducts that are sound do not require removal and can be protected from damage by being enclosed by walls or sturdy boxes . If asbestos is enclosed, the fibers usually are not released into the air and therefore present no immediate hazard.

Friable asbestos that is beyond repair should be removed by a qualified asbestos abatement contractor. Hourly rates run from $200 to $400; estimates are usually quoted by the job.