Asbestos is a set of six naturally occurring silicate
minerals which all have in common their eponymous asbestiform habit: i.e. long
(roughly 1:20 aspect ratio), thin fibrous crystals, with each visible fibre
composed of millions of microscopic "fibrils" that can be released by
abrasion and other processes. They are commonly known by their colours, as blue
asbestos, brown asbestos, white asbestos, and green asbestos.
Asbestos mining existed more than 4,000 years ago, but
large-scale mining began at the end of the 19th century, when manufacturers and
builders began using asbestos for its desirable physical properties. Some of
those properties are sound absorption, average tensile strength, affordability,
and resistance to fire, heat, and electricity. It was used in such applications
as electrical insulation for hotplate wiring and in building insulation. When
asbestos is used for its resistance to fire or heat, the fibers are often mixed
with cement or woven into fabric or mats. These desirable properties made
asbestos very widely used. Asbestos use continued to grow through most of the
20th century until public knowledge of the health hazards of asbestos dust led
to its outlawing by courts and legislatures in mainstream construction and
fireproofing in most countries.
Many countries have discontinued these uses since the health risks of asbestos became apparent. However, their legacy is that many buildings more than 20 years old contain asbestos. It’s estimated that 94% of hospitals in London contain asbestos, and it can also be found in older homes. It does not pose a danger unless disturbed, but can be costly to remove
For more information
Visit https://en.wikipedia.org/wiki/Asbestos
Visit http://www.compoundchem.com/2018/08/14/asbestos/
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