For safety, actual firefighters were on set whenever fire sequences were in progress. In fact, the men in uniform without speaking roles were actually Baltimore firefighters. "They were ready to go at any point," Russell explains. "If anything had really gone wrong, they would have been on it."
On two occasions, Russell admits, the fire explosions "went off a little bigger than we expected. Nobody got hurt making the movie, I'm happy to say." Russell did describe a couple of close calls, however: "At the beginning of the movie there's a floor collapse and Joaquin is sucked into the hole that is created by the collapse. If you look closely on the film you'll see a piece of flaming debris fall within a couple of inches of his face and another one fall on his back, catching his jacket on fire. A split second later he had six firefighters on him, putting him out before he knew he was on fire."
The other incident occurred when Phoenix got too close to flames coming through a doorway. "It hit him right in the face mask, rolled over his head, and you can see it on the helmet," recalls Russell. "You can see the smoke pouring off it. Thank goodness he had his face mask on. It was when I stopped letting him get that close to the fires."