Lenny Richter: Why does it always have to be the 12th floor? Why can't they be on the 4th?
Chief Kennedy: Hey! What the hell is going on in here! Huh? I come back from tellin' a mother her son is dead, and this is goin' on, in my house, in MY house! We deal with this by stickin' together. We take it. We learn from it. And we get back on the god damn truck and that's how we honor Dennis. You got that? Anyone think about lowering the flag? Do it.
Lenny Richter: I'm getting too old for this shit.
Linda Morrison: Have you ever considered baby-sitting full time?
Chief Kennedy: What do you think I do at the firehouse?
Ray Gauquin: No more beer for Linda. Doubles for Jack - he's gonna be a father.
Answer: I'm not a fire fighter so I do not have a answer based on experience but I assume that when Jack was disoriented it's because there was no light in the building, then when the fire broke through it produced enough light to break through the smoke and make seeing easier for him to escape.
It actually doesn't break through the floor...it's a flashover where everything including the gases in the smoke reach their ignition temperature simultaneously and the room lights off...it's a very serious and dangerous situation to be in as a firefighter...I was in one, luckily we were only 10 feet inside the door.
Steve Kozak