Driving on chrysotile? It is possible and extremely
probable, because a considerable number of roads of Quebec have been covered
with asphalt containing chrysotile since 1917. And contrary to some people
still believe today, asphalt containing chrysotile (approximately 1,5 %) does
not release significant quantity of fibres in the environment. It is useless
and ridiculous to think that living close to the road containing chrysotile
will cause death. It would be more logical to fear the emanations released by
the cars circulating on these roads.
Why adding
chrysotile fibres in asphalt? Simply because these fibres increase wear
resistance (the cracks and rutting), without loss of stability. It also
increases the flexibility and frost resistance of the asphalt. Despite the fact
that the costs of implementation are a little higher (approximately 5%), all
things considered, chrysotile fibres confer impermeability, flexibility and
strength to the asphalt. It represents an ideal solution for roads having an
important flow of circulation. As the durability of this coating can reach the
double of the traditional coatings, the increase of cost is easily absorbed
over the lifespan of the road and represents substantial economies for the
taxpayers.
To add
chrysotile to bitumen, the technique is quite simple. First, one has to pour,
in the mixture, the chrysotile fibre bags especially conceived for this use.
The bags of plastic will melt in the bitumen carried at high temperature, thus
avoiding the risk of fibres releasing in the air. Thereafter, once the
aggregates are introduced into the mixture, it is time to apply the asphalt on
the road. Please note that recent data show that the installation of
chryso-asphalt is without danger for the health of the workers; the fibres
release in the air naturally does not exceed the level present in the
environment. Even in situations known as extreme and not very probable (dry
scarification), chrysotile fibres release in the air are five times lower than
the standard prescribed by the World Health Organization, which is 1 fibre/cc.
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Chryso-asphalt products
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