UV bulb not glowing

Simply put: Is it possible that some UV bulbs (specifically the 9W 2PIN
CF-like model that fits a Jebo UV-H9 sterilizer) do not emit any light
when under tension? I know that UV light is invisible to the naked eye,
but I would expect some blue glow at the beginning of the UV spectrum.

I recently bought a pair of these used Jebo sterilizer and I would like
to know if they are working and/or if the new UV bulbs I bought
separately are broken. I started by buying a 9W white CF bulb and plug
it in the sterilizer. Since it wasn't glowing, I thought the ballast in
the sterilizer might be the problem. But then I also tried the UV
bulbs in a small lamp that uses the same 2PIN bulb-plug and is also
rated 9 watts and they didn't glow anymore then in the sterilizer.

At this point, I suppose that the UV bulbs are working; it would be too
much bad luck for me to buy a pair of new bulbs and find that they are
both broken. I also suppose that the ballasts for UV bulbs and normal
Compact Fluorescent bulbs are not interchangeable even though they are
both rated at 9W (am I right on this one?). But if the bulbs aren't
broken and they don't generate any light, how can I know if the
sterilizer is working? Is there any cheap and freely available
material that reacts to UV light that could tell me that the whole
system is working? Anyone has experience with these Jebo sterilizers?
Thanks,

dgee wrote:
Is there any cheap and freely available
material that reacts to UV light that could tell me that the whole
system is working?

White clothing usually seems to "glow" under UV (blacklight). Another
alternative is to go to a local novelty shop that sells blacklights and
get some cheap posters/stickers/paint that glow under blacklight.

Just be careful when testing not to stare into the bulb and give
yourself cateracts. (UV sterilizers are usually much more powerful than
the novelty blacklights.)