It depends on the type of glass and the frequency of the UV.
However, as a guide, 1/8th inch normal window type glass will attenuate
the UV used for photographic work by about one third. So it will work
quite well with circuit boards. You would get the same sort of loss
with an aged UV tube.

Note also that the cheaper UV tubes used for this type of work are
simply fluoro tubes without the phosphor - and they use glass not quartz
for their tube.

David L. Jones wrote:
"John Dough" wrote in message ...

Hi all,

I'm busy building a UV box for photosensative PCB's

I've read various posts about how you shouldnt use glass to cover the
artwork as it stop UV rays. I've also read a few post where they say don't
use perspex - use glass!

Which is it

Is anyone using glass successfully? Or is perspex better? Or nethier - is
there something else I should look at?

Thanks


Glass on my UV box works just fine.
I also get sunburned from the UV though my car windscreen just fine as well.

Dave