The FDNY lost 343 members on 9/11, and many firefighters continue to die from post-9/11 illnesses to this day.

Acting fire commissioner Laura Kavanagh joined Rocco Vertuccio and Shannan Ferry Sunday morning on NY1 to discuss how the department is still dealing with the effects of 9/11.

"We keep losing people," Kavanagh said. "We're still in it. For the fire department, this is very real every day for us."

Kavanagh said the memory of 9/11 continues to inspire firefighters to join the FDNY 21 years later.

"Despite all they've lost, speaking about what service means, what heroism means, what sacrifice means, has continued to draw people to the fire department, year after year, despite all the dangers that they face," Kavanagh said. "And that's a really incredible testament to the FDNY."

On Sunday, Kavanagh began her morning at the Firemen's Memorial on Riverside Drive in Manhattan, attending a ceremony honoring the firefighters lost on 9/11.

"That's a beautiful event. It's an annual event. It's small and very personal in the fire department and something we do every year," Kavanagh said. "So it's great to see the members up there and the right way to start a solemn day."