Exploring of Asbestos

Exploring of Asbestos

Asbestos (Greek a-, "not"; sbestos, "extinguishable") is a group of

fibrous metamorphic minerals. The name is derived for its historical

use in lamp wicks; the resistance of asbestos to fire has long been

exploited for a variety of purposes. It was used in fabrics such as

Egyptian burial cloths and Charlemagne's tablecloth, which, according

to legend, he threw in a fire to clean.

When asbestos is used for its resistance to fire or heat, the fibres

are typically mixed with cement or woven into fabric or mats. It was

used in brake shoes and gaskets for its heat resistance, on electric

oven and hotplate wiring for its electrical insulation at elevated

temperature, and in buildings for its flame-retardant and insulating

properties, its tensile strength, flexibility, and resistance to

chemicals. However, the inhalation of some kinds of asbestos fibres is

now thought to cause various illnesses, including cancer, and thus

most uses of asbestos are banned in many countries. Fibre glass has

been found to be a suitable substitute for thermal insulation and

woven ceramic fibre performs as well or better as an insulator of

high-temperature electrical conductors.

Most respirable asbestos fibres are invisible to the unaided human eye

because their size is about 3.0-20.0 µm in length and can be as thin

as 0.01 µm. Fibres ultimately form because when these minerals

originally cooled and crystallized, they formed by the polymeric

molecules lining up parallel with each other and forming oriented

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... sealed areas already dangerous to

human beings, instead of simply when it might be used as insulation in

a ventilated area, or other similar cases which actually expose it to

people against their will.

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Where asbestos has been banned, its roles must be taken by products

which are often either inferior, or far more expensive. This has a

negative impact on society as a whole, which (especially if the

previous arguments are true in whole or part) may be greater than the

benefit of its removal. In fact, as with DDT and CFCs, some of the

promotion of the ban has been financed by the very companies which

sell more expensive or less effective alternatives, leading to an

ironic charge of corporate greed as the motivation behind

environmental concerns.