"Victor M. Martinez" wrote in message
...

Ok. Now... those bulbs say they last for 5 years or so. Do I still need to
change them after 6 months?

Yes. They are the same as any other compact fluorescent tube,
except that the ballast is built into the socket. So, their light
output deteriorates at the same rate as any other fluorescent.

However, it seems that the 6 months replacement time commonly
quoted for fluorescent tubes is too conservative, at least for some
tubes. 6 months corresponds to around 2,200 operating hours (at
a little over 12 hours per day). Looking at the graphs published
by Osram for the Lumilux T8 tubes, we find that, after 12,000 hours,
we still get 90% of the original luminous flux. In fact, even after
over 20,000 hours, the graph still shows nearly 90%.

I don't know how these figures compare with fluoros from other
manufacturers. But it might pay for you to check out what
your tubes are claimed to do -- you may be able to stretch out
the maintenance interval quite a bit.

Cheers,

Michi.

--
Michi Henning Ph: +61 4 1118-2700
Triodia Technologies http://www.triodia.com/staff/michi