One additional critical factor would also be the UV transmission ability of
fused silica. Here's Clive's ozonizer, so the fact that it works, means that
the 184.9nm line is passing through the quartz tube:
http://www.emanator.demon.co.uk/bigclive/ozone.htm
Indeed, if you connect the burner in series with a 10-15 kOhm resistance so
that it operates in glow mode, ozone gets generated, so again, the quartz tube
is essentially transparent to the 184.9nm.
I am not sure how much of the lower radiation (< 184.9nm) will make it through
the quartz tube. It conceivably may, but then it will be absorbed by air, as
mentioned above.
Vic had given some links about the UV transmission curves for the quartz used
in discharge tubes long time ago, but I can't find them. I believe radiation
below 184.9nm will likely be close to the boundary of fused silica's ability
to pass UV through.