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Sunday, 4 September 2011

Asbestos

Asbestos is actually a type of stone made up of six naturally-occurring silicate minerals, not a man-made material.

Asbestos was originally believed to be the wool of the salamander.

Asbestos (tremolite) silky fibres on muscovite from Bernera, Outer Hebrides.

In 1827 a Mr. Chaubert volunteered to test a new heat-resistant material called asbestos. He carried a raw steak into a large oven in Paris and emerged 12 minutes later very hot but unharmed. The steak was very well done.

Until the 1970s, asbestos was used extensively in fireproofing and insulating buildings in America, among other uses. However, growing evidence of respiratory ailments due to asbestos exposure led to limits.

There are two types of commercial asbestos. ‘White’ asbestos is made from sepentine and ‘blue’ asbestos from sodium iron silicate.

In the production of asbestos, fibers are woven together or bound, but over time they can work loose. Because the fibers are small enough to float freely in the air or be inhaled, asbestos usage is now strictly controlled as exposure to its dust can cause cancer.

Today laws in the US proscribe the use  of asbestos and its disposal and workers who get near it wear ventilators and protective clothes. The European Union and Japan have also banned the fibrous, silicate mineral.

Source New York Times



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