It was the first day of school. Joel Klein, a 30-year New York Local 3 journeyman wireman, was on his cell phone outside a diner asking his ex-wife if their children got off to school smoothly. Then he saw a plane hit the World Trade Center nearby.

"I thought it was a commercial being shot as I didn't hear a sound," he says. His ex-wife said she heard on the radio that a small plane had hit the trade center complex. "But I knew I saw a full-size jetliner," says Klein, who, 13 years later, still cringes when he sees planes fly over his small West Village apartment in Manhattan.

After the second plane hit, Klein, who had worked on the World Trade Center as an apprentice, saw the back of the building blow out. He quickly mounted the bicycle he had taken to work and headed down the West Side Highway toward the trade center.

"The image I remember is seeing people running one way and firemen running into the building [ruins]," says Klein, who on that day had been scheduled to work splicing fiber optic cable in a nearby manhole.

By the time he arrived, the World Trade Center had toppled. That afternoon, a stranger threw Klein a set of keys for a flat-bed truck to take into the chaos to help the volunteers. He couldn't get past the military and state police checkpoint. Neither could truckloads of ironworkers and others who wanted to help save lives. Klein ended up sleeping near the site and offered to assist Salvation Army volunteers the following day.

"But there were no people to help," he says.

Klein worked at Ground Zero for three months for a contractor whose main client was AT&T, one of the companies whose infrastructure was destroyed in the explosions.

Three of the 17 Local 3 members killed on 9/11 were in Klein's apprenticeship class and one was a high school classmate. Four members of Local 1212 also died.

"I went to the funerals, but wanted to do more," he said. So, two years later, as the trade center was being rebuilt and a museum and memorial were rising, he constructed five flags out of wood and a special one to commemorate his fellow Local 3 members who died.

Klein says he's always been moved by the beauty of the nation's flag and the sacrifice of those who have fought in its wars.

Eight feet long and four feet wide, the flags, painted and distressed on wainscot paneling, carried 17 stars for each union member who died in the carnage. On the flag, constructed in a friend's studio, he inscribed, "We Went to our Jobs, Fathers and Sons."

Klein's original plan was for one of the flags to be placed inside Local 3's union hall. It was too large to find a place for, so he ended up convincing the local's motorcycle club, of which he is a member, to place it in the club's meeting room in the hall's basement. And there it stayed until he offered it to the 9/11 memorial and museum, built by Local 3 and the N.Y. building trades.

Today, Klein's flag is not only prominently displayed inside the memorial and viewed by thousands of visitors each week. His flag's image has been imprinted on cups, T-shirts and hats sold at the museum.

Every Sept. 11 since the memorial's construction, rescue workers, including Klein, have been invited to gather there. He says he is moved by their tears.

Lou DiBacco, a 25-year Local 3 member was working with Klein on 9/11 and became his foreman at Ground Zero. "I think Joel did an amazing, touching thing when he made the flags," DiBacco says.

When the flags were placed in the museum, says DiBacco, electricians joined firemen and policemen in the commemoration of the tragedy, a continuing nightmare for many workers who suffer the effects of toxic exposure at the Twin Towers site.

"It was electricians who got the stock exchange up and running and repaired the infrastructure," says DiBacco, who has had two nonmalignant tumors removed from his esophagus and brain that his doctors suspect came from exposure to toxins at Ground Zero. Today, he works as an electrician for the City of New York in firehouses and firemen training centers.

Klein says he stays busy since his retirement nine years ago. A longtime balloon twister, he was invited to the White House a few years back on July 4 to participate in a Wounded Warriors benefit. And he's written a couple of musicals and plays.

And he still thinks about the cooperation and camaraderie that followed the tragedy of 9/11.

"I'm 64 years old," says Klein. "In a strange way, I related the support that came from all over the world to help after 9/11 to Woodstock. I got a sense that an unbelievable change was happening in the world."