[ohitsdom]

> UV ends up not being worth it because you'd have to replace the bulb almost on a monthly basis.

I have a UV system on my home A/C, and the bulb usually burns out once every two years (and it's always on). I'd imagine this would be greatly extended if in place in a car when it's not always on. Am I missing something?

[votingprawn]

The effectiveness of a UV lamp decreases with age, so they can stop being effective long before they actually burn out. There should be a manufacturer rating on the lamp, which will depend on its composition and other things.

As an example the lamps I use have a rating of ~8000hrs, about a year, but to the outside observer they'll still look functional until they blow after 2-3 years.

[toomuchtodo]

Do they have UV LEDs yet?

[retbull]

I thought that turning lights on and off is most of what causes damage to them.