Tube amp on/off: best practice?

My main system, with a tube integrated, is in my studio where I work 10-12 hours a day, interrupted by the occasional offsite meeting or errand.

What's the best practice/rule of thumb for powering it up and down as I duck in and out of the studio? Just leave it on all day?
How long do I need to be away for it to be better to power it down?

Right now I'm firing it up and cooling it down about 3x a day, running it a total of 6-8 hours a day.
I agree with Elevick completely. I've had many tube amps over the years. One of which had a output tube go bad. Music was not playing, but there was a god-awful screech coming out of the left channel, then I saw a red flame shoot up through the top vent, followed by smoke. Thank god I was home. I lived in a condo and I don't want to think what could have happened to the seven other families in the building. I've been using digital amps for a while now.
ok, so here's another reason I don't want my lovely wife reading Audiogon.

Thank you guys for the reality-check.
I leave my pro-ject tube phono preamp on all the time. Is this ok?

Rest of my system is Audio Refinement SS gear.


If you listen all day, and turn it off at night, that's fine; but it's realy not good turning tube gear on and off like you describe, and I forget why or why not.