(NEW YORK) -- As the nation marks 10 years since the attacks of 9/11, the New York City Fire Department is preparing for what its leader says will be a "tough day."
As a reminder of the attacks, FDNY Commissioner Sal Cassano keeps a framed poster on his wall with the names and faces of all 343 firefighters killed on Sept. 11, 2001.
"We were the first soldiers in the war on Sept. 11; we were the first in battle, and every day we are driven by the lives that were lost," Cassano says.
"I gave orders to a number of people in that building and not once did any one of them flinch," he says, referring to the firemen inside the Twin Towers at World Trade Center.
As firefighters rushed in, their radios went dead.
"Ten years later, despite all the improvements that we've made in our communications system, it's something that nobody would ever say we've got a perfect system," Cassano says.
But Cassano says the radios are better today, as is the department's training and mindset.
"We have to be prepared for anything that's going to come our way. We just don't fight fires anymore," he says.
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