Change CF bulbs every 6 months because...

[Chelsey]

I once read somewhere that compact fluorescent lighting (bulbs) should be changed every 6 months. I've been doing that, but I don't know why. Why do the bulbs need changing?

 

[smleee]

The color spectrum of the bulb will start to shift after 6-9 months. Also, the light output will start to decline after 6-9 months (part of this is due to the color shift). Essentially the light just don't have the output they did when they were new. You really can't tell how much you've lost until you have a brand new bulb plugged in beside the old one. In some cases I have waited 12 months and the difference is incredible.

eee