Denis Leary did not want to run his Leary Firefighters Foundation like a typical celebrity fundraiser, he said—no golf tournament and no auction. Instead, Leary partnered with the Fire Department of New York and the FDNY Foundation to create what he called a “crazy idea” for International Firefighters Day: a “Firefighter for a Day” program that puts civilians through training at the FDNY Fire Academy on Randall’s Island in New York City.

Leary said the concept worked from the start, telling The Associated Press that “It was exciting from the get-go,” adding, “Now, 10 years in, it just gets better and better every year. It’s truly amazing.” Since 2016, he said the program has been the only day each year when the FDNY Fire Academy is open to non-firefighters, giving them a hands-on look at emergency response training.

Participants train with actual FDNY firefighters, and the day includes practical exercises such as rush drills into burning buildings, carrying fire hoses to extinguish flames, and searching for survivors. The training also includes rappelling down buildings to reach safety, according to the AP report describing the event.

Leary said participants are not forced into anything they do not want to do. He added that once civilians see the teamwork and expertise involved, many choose to do more than they initially planned, including tasks they may have skipped at first.

As an example of that shift, Leary recalled how “The Good Wife” star Julianna Margulies came to the event one year intending to coach rather than participate, leaving him with her new team. Leary said Margulies later returned “in full bunker gear,” describing that she “just rappelled down the side of the building,” and he said his response was, “What are you talking about?” Leary said Margulies answered, “I know! I overcame all my fears.”

David Morkal, a retired FDNY battalion chief and a board member of the Leary Firefighters Foundation, said the annual event draws “a lot of actors,” along with athletes and corporate supporters, and that the fundraising each year allows the foundation to make additional grants. Morkal told AP that grant amounts have grown from around $200,000 a year when the effort began a decade earlier to about $850,000 now, and that the foundation hopes to reach $1 million in grants this year.

Morkal said the foundation’s grant criteria have remained the same since Leary started the foundation in 2000 following a tragic Worcester, Massachusetts fire that killed six firefighters, including Leary’s cousin and a childhood friend. He said the mission is to provide departments with equipment and training to help firefighters “walk away from a fire after it’s out and go home to their families,” describing the work as “training and equipment.”

John Tyson, assistant fire chief at the Talladega Fire Department in Alabama, said one piece of equipment his department received from Leary’s foundation—a forcible entry trainer—has been used “almost every day.” Tyson described how the device helps firefighters breach locked doors more quickly, though he also said it can be hard for smaller departments to find budget space for high-priority needs.

Tyson said he believes people value the fire service, but do not always recognize that first responders still need support. “We’re a small department in rural Alabama,” he said, adding, “It’s touching to me that someone who has achieved the success he has still wants to give back.”

Edward A. Kelly, general president of the International Association of Fire Fighters, said he wished the Leary Firefighters Foundation were unnecessary—because fire departments should have the equipment and training they need without relying on philanthropy. Kelly said fire departments operate under budget pressure as city governments weigh competing demands, and he described the foundation as standing in “the giant void” created by those constraints.

Kelly said the union has credited the foundation with supporting fire departments over its 26 years of gifts, and he told AP, “We owe a great debt of gratitude to Denis and to all the people that have helped support the Leary Foundation.” He added that “Whatever will fill the gap that will prevent the next tragedy is well worth the investment.”

Leary said that after the Sept. 11 terrorist attacks, he briefly hoped the federal government would step in to make the foundation less necessary, describing “a brief moment” when people wondered, “Is the government gonna step in?” He later said that hope faded, and he continued to work on the foundation anyway. He also said he has drawn inspiration from his friend Boston Bruins hockey great Cam Neely, now the team’s president, and from Neely’s work supporting cancer patients at Tufts Medical Center.

Leary said he first saw Neely as someone who proved that fame can be used to make a difference. “So by the time I had to do something, I had a good example of what you can use fame for,” Leary said.