To reiterate what others have said, it's fairly small for an NPC, and more than a few minutes if it's a PC. If you time it once you'll get a more precise idea.

I got some great advice from various imms on this forum when I started playing that amounted to:

Carrionfields needs a little more scheduling than other online games. The PK and RP requirements mean that there really isn't an emergency quit button. You probably should have a 'wind down' period before you actually need to log out, even if that means you log out early.

If it's really something important and a really sudden and unforeseen emergency, don't worry about the game. Do what you have to do, because...jumping in an ambulance, getting to class, taking care of your kid, or doing your job is just way more important. The game will be here when you get back and scheming to regain a piece of eq you lost will just give you another goal to entertain you.

Given potential for abuse, it's my personal opinion that not having an emergency exit is probably a good thing, despite the occasional burden it puts on those of us who are playing.