The way through the flames

Firefighters are specifically trained to deal with disorientation. In near-black conditions, they often use hoses or search ropes to find their way back to safety. Without tethers, they follow the “right-hand rule,” running the fingers of one hand along a wall until they reach a door or window through which they can escape. The two lost firefighters didn't have ropes, and their right hands presumably led them only deeper into the warehouse's labyrinth. When they realized they were lost, they did what they'd been taught to do: They stopped moving, radioed for help, and activated the personal alert safety system (PASS) devices attached to their air tank harnesses. These battery-powered boxes emit a piercing alarm for rescuers to listen for.