fluorescent tubes and ambient temperature

[hl68fx]

Hi everyone,

I would like to use fluorescent tubes in some kind of furnace. Can you tell me what happens to these lamps being used in an ambient temperature of 80 to 100 °C?
What happens to light output and lifespan? Will it be possible at all?

Kind regards
Tom

[Jwillis]

Fluorescent tubes are very sensitive to ambient temperatures .Light output drops off significantly either direction of 25 to 30 degrees centigrade. For example  exterior lamps go very dim at -20C and again grow dim in very hot  areas.Different Types can be effected differently by ambient temperature.http://www.lamptech.co.uk/Documents/FL%20Temperature.htm and http://www.lamptech.co.uk/Documents/Journals/Thorn%20Lighting%20Journal%203.pdf do a better job of explaining this.

[amyk]

I recommend using incandescent if you need it to withstand high temperatures --- lightbulbs are much hotter than that inside.

[CatalinaWOW]

Another choice is to use a light pipe to bring light in from whatever source floats your boat.  Glass fibers and pipes will easily handle the temperatures you mention.