Name: Cassi P.
Why are car windshields safer than ordinary glass windows?
Today, for greater safety, the automotive industry
employs the laminated glass which consists of
two glasses plates and in-between, a plastic foil made
of polyvinil butyral. Occurring an accident, the glass
will not "explode", but the small pieces will remain
attached over the plastic surface. This is called
You can also find the temperated glass, that has
a great resistance. The heated glass is cooled
very fast and reaches a high resistance degree.
Because of the presence of Nickel Sulfide (NiS), some
glasses after years of use may suddenly "explode".
This is a illness of the glass, but today it is possible
to deal with this problem, with a longer period of
heating (about 6 hours).
Auto glass is tempered, that is, in the manufacture it is cooled in such a
way to improve its strength. The glass used in autos is not the same
composition as window pane, but I don't know exactly what the differences in
composition are. Auto glass is also laminated. The layer between the inner
and outer glass is flexible and keeps the two outer layers from shattering.
However, a caution, the shards of automotive glass are razor sharp and can
cause some nasty cuts.
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Update: June 2012