"John M. Darnielle" wrote in
:

The manufacture of my ultra violet light recommends replacing the
quartz sleeve containing the bulb when the bulb is changed- does it
degrade over time or is there some other reason why it should be
changed? I do clean it every year and replace the bulb every other
year. Thanks in advance for your reply.


Yes, quartz degrades with exposure to UV over time, but the effect is
visible. You'll see a whitening of the clear quartz tube, which is a de-
vitrification effect (not cleanable). The manufacturer is, of course,
grossly over-stating the required rate of replacement, both to ensure that
the unit continues to function well, and also to get more of your money.
Keep an eye on the sleeve (you clean your sterilizer every month or so,
right?). When it starts to look a little milky or hazy to you (read a
newspaper, or the sterilizer's owner's manual, through the sleeve), either
from this effect or due to scratches and other physical damage, replace it
then.

Regards,
R. David Zopf