It’s been 11 years since a terrorist attack brought down the World Trade Center’s twin towers in New York, forever changing the nation and the city’s famous skyline.

For most of the past decade, America has debated what should happen at the attack site — create a memorial for those who died so tragically or rebuild, bigger and better than before. The answer is both.

The new One World Trade Center, scheduled for completion in 2013, will soar above New York City at 1,776 feet. The footprint of the destroyed twin towers serves as the site’s memorial, with large pools and waterfalls placed inside. Inscribed around the edges of the pools are the names of 3,000 people who died in New York City; Washington, D.C.; and near Shanksville, Pa., Sept. 11, 2001.

The rebirth of the World Trade Center is not only historic, but an epic endeavor for the architects, engineers and construction workers involved. It is collaboration on a grand scale, and Eastern Sheet Metal is part of it. The Ruskin-owned company, with locations in Cincinnati and Dothan, Ala., manufactured the sound attenuators for the WTC Port Authority Trans-Hudson (PATH) transportation hub, which provides mass transit throughout the region. The project, with its unique challenges, was a source of pride — and patriotism — for all involved.

Starting the journey

Ventilation and air-control company Ruskin has been working on the new trade center project for the past five years by designing and supplying dampers and attenuators. However, the company’s history with the World Trade Center goes back even further.

According to Michael Wiltfong, industrial and nuclear applications manager for Ruskin Air and Sound Control, the company had sold and installed dampers for the train station below the towers. In fact, the company’s representative, John Davey of Kane-Davey and Associates, was in New York Sept. 11, 2001, to meet with the transit authority concerning the commissioning of the fans and dampers that were supplied for the train station. The events of that day changed everything.

With the new trade center now under construction, Ruskin is working with Kane-Davey, based in Milford, Conn., to supply the ventilation components. For Wiltfong, returning to the World Trade Center for the rebuilding “is flattering for us.”

It includes not only the dampers and fans supplied by Kane-Davey for the WTC’s train system, but also designing and manufacturing attenuators that weigh 7,000 pounds each.   

“There were crazy parameters,” Wiltfong said. “These were not your normal attenuators.”

The systems had to be designed to withstand strict testing, including tests for temperature and decibel levels. The attenuators had to eliminate noise not only in the mechanical room, but noise that could travel trough the ducts to other building spaces.

All attenuators have sliding panels, which trade center workers would need to access. Under most circumstances, these panels can weigh between 200 and 300 pounds. But for this project, the panels needed to be lighter so that one person could pull them in and out.

Once Ruskin finalized the design demands, the sketches and specifications were sent off to Eastern Sheet Metal for the building and welding to begin. 

The big build

Mike Mercer, shop foreman for Eastern Sheet Metal in Dothan, Ala., said the attenuator project “was a big challenge.” But not for the reasons many may think.

The project called for the use of 10-gauge, G-165, galvanized steel for the attenuator casings, and 4 by 4 by ½-inch angles for the connections. All much heavier than the typical duct Eastern Sheet Metal deals with.

But for the crew at ESM, this was no big deal.

“They’re use to building big stuff,” Mercer said. He explained that many of Ruskin’s ESM employees have welding backgrounds working on projects that call for heavy steel, such as highways and bridges.

The first real challenge for Eastern Sheet Metal was obtaining the 10-guage steel with the G-165 coating. It had to be ordered from the mill and took approximately 10 weeks for it to be delivered. However, once it was received, Mercer said “there was nothing to it. We had fun.”

However, the “fun” did take some time. The welding began in December 2011, and the final attenuator shipped to New York City in June 2012.

The job fluctuated between six and seven workers depending on worker availability. The project required some workers to put in overtime, including Saturdays and Sundays, to make deadlines.

Each of the attenuators that were welded together consisted of three sections. Most of the systems were 12 feet by 12 feet by 12 feet, while a few others varied in dimensions. Those three sections were then fitted together at the World Trade Center site.

Size restraints

While the welding of the attenuators wasn’t a major challenge, the sizes of them did create some difficult situations. Special permits were required in order for trucks to ship the attenuators north. This was because the attenuators hung over the sides of the trucks. According to Mercer, the truck drivers didn’t just need one special permit, but permits for each state the truck went through on the way to New York.

Once some of the attenuators reached Manhattan, more challenges presented themselves. The attenuators are located below the WTC train station. Construction crews opened a hole below the station to lower the equipment into place. However, some of the attenuator dimensions were too big to be lowered down in one piece.

With looming deadlines and other trades needing to start pouring concrete, crews decided to cut the systems apart and reassemble them underground.

“This meant that we needed to fabricate some extra unique parts to help with the reassembly,” said Mercer.

Celebration

Despite difficulties and unforeseen circumstances, the attenuator project for the World Trade Center was a source of pride for Eastern Sheet Metal.

The first finished attenuator was shipped out to New York City last year, but not before workers commemorated the event with a bit of patriotism. Before the attenuator was loaded on the truck, one worker said “We got to have a flag,” Mercer recalled.

The company tracked down a flag, unfurled it, and used it as a backdrop while the workers’ crowning achievement was lifted on to the back of a truck.

For the welders who worked for over a year on the attenuators, the project was more than a job. Mercer said it was their way of giving back just a little of what had been lost more than 10 years ago.

“It was a real humble feeling,” he said.