-- Firefighter Sal D'Agostino on the "special club" who were inside the towers when they fell and survived.
 15 seconds of hell
K-9 officer lives through North Tower collapse

David Lim and his K-9 partner Sirius, a yellow Labrador, before September 11. Sirius was crushed by the collapse of the South Tower while Lim was helping firefighters in the North Tower. 

NEW YORK (CNN) -- David Lim knew things were bad when he clambered up the North Tower stairs and looked at those going down -- some burned, others bloodied, most fearful. But the Port Authority police officer thought everything was in control: He had worked at the World Trade Center for 19 of his 22 years on the force, and it wasn't going anywhere. 
Then around the 34th floor, he heard the rumble and felt a whoosh of air. The South Tower had collapsed: It didn't take long to realize the North Tower could be next. When he arrived on the fifth floor, he spotted firefighters from Ladder Company 6 helping a grandmother from Brooklyn, Josephine Harris. He jumped in and with the others took hold of her and slowly headed down a flight of stairs. Then it happened: The horrific sounds, crunching crashes and choking dust, as 110 stories of steel, concrete, equipment and people collapsed on top of them. "I knew it was our building, because there was nothing else left," said Lim. "It lasted about 15 seconds, but it felt like forever." A floor lower, a floor or two higher, and he might be dead. But Lim, Harris and firefighters Mike Meldrum, Matt Komorowski, Bill Butler, Tom Falco, Sal D'Agostino and John Jonas were somehow alive in Stairwell B on the fourth floor. Five hours later, with the aid of Lim's cell phone, help from Ladder Company 43 and plenty of personal resilience, they poked through what would have been the stairwell's sixth floor. As he crawled over the debris field to safety, Lim cried out for his K-9 partner Sirius, a yellow Labrador that he had last seen in the South Tower. In the subsequent months, Lim and his new comrades from Ladder 6 were hailed as heroes for running into the North Tower and successfully urging hundreds to safety. But Lim said he is hesitant, and maybe too lucky, to embrace the label. 
"The reason we took this job is because people needed our help," he said. "I did my job well that day, but I don't know if I'm a hero. I think the people who died that day were heroes." 

Losing a partner and a 'second home'

Lim and his new K-9 partner, Sprig, who is trained to detect explosives. 

David Lim was born in New York City on September 2, 1956, a decade after his parents left China for the United States. Inspired by the cops who frequented his parents' Chinatown restaurant, he determined at an early age that he wanted to become a police officer. By 1980, his dream had become reality, as he worked the World Trade Center beat for the Port Authority police department. Spurred by the 1993 bombing, he joined the K-9 patrol in 1997, clearing VIP areas and checking trucks for explosives. After his first explosive detector dog, Lena, retired, Lim partnered with Sirius in 2000. Sirius was with Lim in the South Tower at 8:45 a.m. on September 11 when American Airlines Flight 11 slammed into the adjacent building. "'I'll come back for you, I promise,'" Lim recalled telling the dog before heading into the North Tower. "I locked the kennel, closed the door and that was the last I saw of him." Last spring, rescue workers draped Sirius' body in a U.S. flag as they pulled him from the rubble -- the same treatment afforded police officers and firefighters. Some 400 people -- plus 100 rescued dogs with their handlers -- attended a memorial service in April for the fallen Labrador. "He did the job like the rest of us, and gave his life that day," said Lim. "In my mind, he'll always be a hero." Lim lost many other friends that day. After nearly two decades there, he says the World Trade Center had become his "second home," and those who worked there his extended family. He also takes pains to remember the 37 Port Authority police officers, 23 New York police officers and 343 firefighters killed on September 11. From his current post on the New Jersey end of the Holland Tunnel, with his new K-9 partner Sprig, the skyline serves as a daily reminder of last fall's attacks. "You've got to remember that from most anywhere in New York or New Jersey, you could see the World Trade Center," said Lim.
"All you have to do is look and not see the towers." 

Emergence as a role model
But in other ways, Lim's life has changed for the better. 

He has become a spokesperson for Port Authority police and Asian Americans. At an Asian cultural festival on August 18 in Denver, Colorado, attended by 30,000 people, Lim said he relished the chance to be a role model for Asian Americans interested in law enforcement. "We have role models in journalism and in politics," Lim said. "Perhaps one day when your child (tells) you, 'I want to be a police officer,' you'll say yes, because you know that we can do good work, and work as a people in this line of work." The father of two from Lynbrook, New York, has also forged bonds with the six firefighters he shared close quarters with amid tons of North Tower debris on September 11. One of those firefighters, Mike Meldrum, was drifting in and out of consciousness after being thrown during the North Tower's collapse. Lim talked constantly to Meldrum to keep him awake -- a medical must for those who suffer concussions -- and offered his cell phone and World Trade Center expertise to the firefighters, said Meldrum. "We stick together and we do what we're supposed to do and with David -- it was just like another piece of the puzzle," said Meldrum. Sal D'Agostino, another Ladder Company 6 member, called Lim a "very close friend" and a member of a "special club" -- those who were in the north and south towers when they fell and somehow walked away. "There are only 14 people on this Earth who know what it's like [to be] in a 110 story building when it collapses," says D'Agostino. Lastly, Lim has forged a connection with many children after speaking at various schools and camps this summer. At a talk at Camp Saejong in northern New Jersey, a program for young Korean-Americans, camp co-director Lindy Gelber said the campers immediately picked up that Lim was "an average man who rose to an extraordinary challenge." 
"Being a hero means taking a risk, and that's exactly what David did," said Gelber.
"They look and say he is just like me, and I am just like him. I can do that."