Warwick wrote:
[...]
Toughened. The glass is more difficult to break, but when it does
it
turns into mostly small cubes of glass (such as you see after a car
accident or break in). These cubes are much less likely to injure
and
you'll be clearing them up forever. (I imagine that cutting the
stuff
to size is an interesting process)
[...]

I found out that one of the reasons it's expensive is that it has to
be cut to size before being tempered by going back into a kiln. But
the actual cutting, the man told me, isn't any different from cutting
ordinary glass.

panes. I've resorted to sticking a plastic coating to the outside
of
any pane that our toddler could plausibly break.

I did that, too, way back: it was reassuring at the time, but I often
wonder how much difference it would have made.

Mike.