People don't know what to do in case of an emergency building evacuation. I was a fire warden at our previous office for nearly three years and I was still vague despite six-monthly training. Everyone else's idea of procedure is considerably less informed.
Buildings in Queensland (and probably all of Australia) have two-stage evacuation alarms. The first sound you'll hear is a constant tone, often written down as "Beep-Beep-Beep". On this tone, the fire wardens get up, put on their hats and look around for hazards. You, as a non-fire-warden, gather your belongings, lock your computer and stay in your seat to keep out of the wardens' way. Most people, rather than sit still and wait, get up and walk out the nearest door to mill about aimlessly or follow the first crowd they see. Often, this is not a big problem, but it is against standard procedure for a reason.
First of all, what if the danger is outside and your best course is to stay in? You are walking straight out into danger because you didn't wait for anyone to do their job and keep you safe. Second, what if the danger was in a hallway and, because you don't pay attention to stupid emergency evacuations, stumble straight into it before the wardens can determine a safe evacuation route and direct you there? Again, dead because you hate waiting. Third, you might not need to evacuate at all, in which case you're wasting time.
In short, everyone please remember that you don't evacuate until the rising tone, usually written down as "Whoop-Whoop-Whoop".
Mokalus of Borg
PS - Unless your building has a different procedure for some reason.
PPS - Such as being located in another country with different regulations.