NEW HAVEN, Conn. (WTNH) – The chief of New Haven’s Fire Department has spent time responding to Ground Zero following the 9/11 terror attacks. News 8 spoke with him about his experience and how it changed him forever.

Before he was New Haven’s Fire Chief, John Alston was a firefighter in Jersey City, right across the Hudson River from the World Trade Center.

“Grew up, went to school downtown Jersey City. I watched the buildings go up when they were building them, and I watched them come down as an adult,” Alston said.

On 9/11, he rushed to work and heard firefighters inside the tower still talking on their radios as the unimaginable happened.

“We were stationed downtown Jersey City. We watched them just dissolve,” Alston said.

Alston and his team then got sent across the river. After officials cleared everyone away from 7 World Trade Center, Alston was there as that 47-story building collapsed.

“You don’t forget that. The sound, the noise, the dust that chases you up the street,” Alston said.

Then came days of working “the pile,” searching for survivors and finding mostly remains.

“The New York City firefighters would go in, and they would go to that area, and we would all stop, and they would dress the body in the flag. We would all salute and they would bring them out,” Alston said.

There were 343 firefighters who died in 9/11, a loss felt by all firefighters everywhere.

“What unifies us is this uniform, is the badge, is the patch, is the promise, is the pledge that we’re here to serve others,” Alston said.

Just this past May, Alston saw that when he lost one of his own. Firefighter Ricardo Torres died in the line of duty. The FDNY helped organize the funeral, and his former colleague from Jersey City, was right there, too.

“I don’t know they did it, but they were the first group we saw when we turned onto the street. That meant the world to me,” Alston explained.

The grief of losing colleagues haunted Alston for years after 9/11. He tells everyone suffering to get professional help.

“And so, I always encourage people to seek counseling, to talk to someone. To navigate grief, we are not designed to do it by ourselves,” Alston said.

There is also the physical toll of working the pile. Ground Zero air has now killed more first responders than the collapse of the towns. So far, Alston remains healthy. He goes back to New Jersey all the time, looks over at the new Manhattan skyline and remembers those lost.

“To honor them is to live the best that we can. That’s how we honor them,” Alston said.

We can also remember that their sacrifice was not in vain. Thanks to the work of firefighters, thousands of people escaped the World Trade Center on 9/11. As Alston says, a firefighter has to be willing to trade his or her life for the lives of others. That’s why we call them heroes.