Asbestos is a general term given to a group of six naturally occurring minerals popular in commercial use. Asbestos is used in various commercial products for its strength, flexibility, low electric consumption as well as heat and chemical resistant qualities. It is composed of silicon, oxygen, hydrogen and various other metals.
Although asbestos is the generic name for six natural minerals, yet, it still can be divided into two basic groups depending on the form in which it is found.
- Serpentine asbestos which develops in layered form
- Amphibole asbestos which has a chain like structure
Common Types of Asbestos
Asbestos can be further divided into various types depending upon how it occurs and affects the human health. This helps in identification of the specific fiber type of the asbestos and determining its properties and dangers to human health.
There are 3 types of asbestos which are most common and easily recognized.
Chrysotile (white asbestos)
Chrysotile is a while curly fiber, obtained from serpentine rocks, found in layered forms. As it can be spun and woven into fabric, this form of asbestos is most frequently used in industrial capacity. It has been found that chrysotile accounts for 90% of asbestos usage. Chemically chrysotile is known as magnesium silicate.
 Being more flexible than any other type of asbestos, it is used in making curtains as well as firefighter suits and tablecloths. Being an asbestos mineral, chrysotile is harmful to human health. However, evidences suggest that it is not as harmful as other forms of asbestos which are more deadly, as proved by UK Health & Safety Commission report ‘Asbestos: Effects on health of exposure to asbestos, 1985’.
Commercially used chrysotile is usually contaminated with a powerfully hazardous toxic called Tremolite which can cause considerable damage to human health and cause cancer.
In the United States, chrysotile has been the most common type of asbestos used in a wide variety of materials, such as:
- mud and texture coats
- vinyl floor tiles, sheeting, adhesives
- roofing tars, felts, siding, and shingles
- "transite" panels, siding, countertops and pipes
- fireproofing
- caulk
- gaskets
Amosite
 Found in brown or grey colors, amosite fibers are straight and belong to the amphibole group of asbestos. Amosite is an acronym for Asbestos Mines of South Africa as it is commonly found in Africa.
Amosite is very hazardous to human health and exposure to this kind of asbestos leads to mesothelioma. Amosite is used in:
- low density insulation board and ceiling tiles
- casing for water and electrical/telecommunication services
- thermal and chemical insulation (i.e., fire rated doors, limpet spray, lagging and gaskets)
Crocidolite (Riebeckite)
 Crocidolite also belongs to the amphibole group of asbestos and appears in the form of blue straight fibers. Crocidoilte is a sodium iron magnesium silicate. It is mostly found in Africa and Australia.
Blue asbestos is generally thought of as the most dangerous type of asbestos which can do maximum damage to human health. Crocidolite asbestos is used in making cement sheets and pipes for construction.
It has been found that all forms of asbestos are naturally slender and thin as they are composed of fibers which measure less than 1 micrometer in length. They occur in bundles and are very lengthy.
Other Types of Asbestos
Some other types of asbestos which belong to the amphibole group are:
- Anthophyllite - it ranges from white to grey and brown colors and associated with talc and other minerals.
- Tremolite – it is a calcium, magnesium, iron silicate which is found in white to grayish green colors. It is found in metamorphic rocks
- Actinolite – it is similar to tremonlite but actinolite contains more iron than tremolite and appears as dark green crystals or fibrous bundles.
Other non-natural types of asbestos are richterite and winchite. All types of asbestos exhibit physical and chemical resistance to high temperatures and applied force. They are made up of fibrous strands which continue to split in smaller and thinner stands as they are handled. They can become invisible and stay airborne too.
These types of asbestos are used in construction and insulation materials and used in industrial products too. They are equally harmful as other commonly used and found types of asbestos and cause asbestos related diseases. |
