In ,
Andy wrote:

I don't know if this typical for CFL's or for one particular brand.

I replaced 3 incandescent bulbs with 3 CFL's and they all burned up
within 6 months.

The bathroom is small and it has no working exhaust fan.
Has anyone else seen this problem?

There are a few reasons this may occur, and I think humidity is less
likely to be the problem. My suspects a

1. CFLs can overheat in small enclosed fixtures and in downlights,
especially recessed ceiling fixtures (which I call "heat hellholes
for CFLs").
This is a problem mainly to integral-ballast CFLs (includes all
common screw base ones) 15 watts or more. There are ones rated for
use in recessed fixtures, including Philips SLS ("triple arch"
Marathon) non-dimmable up to 23 watts. There are even snap-on
reflectors for these in R30 and R40 sizes.

If you cannot get or use Philips "triple arch", you can try using
a lower wattage and/or CFLs of a "Big 3" brand (GE, Philips,
Sylvania), especially ones with the limited warranty.

2. I have experienced above-average rate of premature failures with
CFLs of the Lights of America brand and of brands that I see mainly
in dollar stores.

3. Although several short on-off cycles per day should not kill CFLs
within a year, a very large number of on-off cycles per day can
kill some in a matter of months. Ones that are true instant start
suffer more wear per start than ones that take half a second or so
to turn on. (This is unrelated to time to warm up once it comes on.)

- Don Klipstein )