Throughout the 20th century, asbestos insulation posed the greatest risk of asbestos exposure to workers and continues to pose a hazardous threat in numerous homes and businesses today. Initially, asbestos was widely regarded as an ideal material for various insulation applications until its carcinogenic properties were brought to light.
The inherent characteristics of this naturally occurring mineral include its unique fibrous composition, giving it a resemblance to cotton. The structure of the fibers creates a barrier that effectively slows down heat transfer, making it highly resistant to high temperatures.
Asbestos fibers have the ability to easily separate, enabling manufacturers to blend them with other substances like magnesia to produce diverse forms of insulation. When insulation was required, asbestos became the material of choice. Consequently, throughout much of the 20th century, those working with insulation were commonly referred to as "asbestos workers" due to their frequent interaction with this substance.
Asbestos-containing thermal insulation can be grouped into four major categories: Loose-fill, wrap, block and spray-on.
Loose-fill insulation is designed to be poured onto attic floors or blown into hollow spaces inside walls and other building structures. Fluffy loose-fill asbestos insulation — sometimes made almost entirely of the toxic mineral — is extremely dangerous because even a slight air current can disturb it, sending inhalable asbestos fibers into the air. This product was also known as asbestos attic insulation.
Insulation coverings for pipes, ducts and other plumbing and HVAC components in old buildings often contain asbestos. Asbestos pipe insulation was also a major health hazard on Navy ships for many decades.
Before 1980, insulators typically wrapped pipes with asbestos-based air-cell insulation, which is essentially a type of cardboard made out of asbestos paper. This kind of insulation becomes crumbly as it ages, releasing large quantities of asbestos dust if it is damaged or cut off to be replaced. A product known as asbestos wool insulation was also wrapped around pipes.
The fabric of old valve insulation jackets also often contains asbestos fibers, which may be dispersed through wear and tear.
One simple way to insulate the wall of a building is to glue a slab of insulation to it. In the past, these insulation blocks or boards were often made of nearly pure asbestos, which creates a major exposure hazard whenever such blocks are sawed or damaged. This product was also known as asbestos wall insulation.
Spray-on insulation was developed to reduce the amount of labor required to apply insulation and fireproofing materials to ceilings, walls and structural beams. You can see spray-on insulation in many large commercial buildings where the ceiling is coated with a thick layer of grey material.
Unfortunately, many spray-on insulation products contained up to 85% asbestos, putting the workers who applied them at extreme risk. Further, these products can be damaged easily, releasing a cloud of asbestos fibers into the air. They present a major exposure hazard unless they are thoroughly encapsulated.
Call Revolve Asbestos Solutions to safely identity and remove any suspicious insulation.