Tuesday, December 28, 2010

Uses in West not relevant to India

The health issues recorded in the Western countries in the past and which are being highlighted and debated by the anti-asbestos lobbies relate to extensive and uncontrolled usage of the Blue and Brown varieties of Asbestos fibre falling within the amphibole category.

Friable low-density asbestos insulation boards were also used as inner roof to provide better fire protection. These products consisted of asbestos upto 90% in loosely bound form. Such applications exposed workers to uncontrolled inhalation of loose asbestos dust in high concentrations which led to health related problems. Once the ill effects of such applications were documented, such usages were stopped in the western countries decades ago.

Those experiences in the West, do not apply to India, where warm climatic conditions never required such asbestos containing thermal insulation of buildings.

In India, we only use Chrysotile (white) asbestos fibre for the manufacture of asbestos-cement sheets and asbestos-cement pipes which contain a very small quantity of Chrysotile fibre (only 8 –10%). The other raw materials used are cement 45%, fly ash 30 –35% and wood pulp. The asbestos fibres are firmly locked-in or encapsulated within the cement matrix during manufacture so that fibres cannot be emitted into the atmosphere under normal use and thus, poses no health risk to the general public or environment. Several studies abroad have concluded that use of Chrysotile in the manufacture of Asbestos Cement Products under controlled conditions is safe for the workers, environment and the general public.

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