The underpass, located at South Gregson Street near Peabody Street, has a clearance of 11 feet, 8 inches.
The bridge is over a local road but the Federal Highway Administration recommends that underpasses should have at least 14 feet of clearance.
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And North Carolina law sets a maximum height for trailers at 13 feet, 6 inches, according to the AAA, well below the height of the can opener.
Lee Gardner, who owns a Penske Corp. truck rental business in Durham, warns drivers to avoid the bridge and tells them any damage caused by the can opener is not covered by insurance.
Gardner also runs a tow service company and says the bridge keeps him busy.
"We hear it every time: 'Hey, you know, I was just following the GPS. Siri was telling me how to get there,'" Gardner said. "And they don't have a truck GPS, they got a regular car GPS," he he added.
Some moving trucks Gardner’s company rents are 12 feet, 7 inches tall — higher than the underpass clearance.
"I sit there at my desk working peacefully and all of a sudden there's this massive crash out there and I almost fall out of my chair," said Henn.
Just after Henn spoke with NBC News on Wednesday, it happened again: A truck too tall to pass beneath crashed.
“I thought I had enough clearance," said the driver, who was shaken but uninjured.
Signs and sensors have been installed near the bridge to warn drivers but the bridge is owned by the railroad company. As for lowering the road, a sewer line runs beneath it. The state Department of Transportation plans to install more sophisticated sensors.
"You'd be looking at significant cost to either lower the road or raise the grade of the railroad," said John Sandors, deputy division traffic engineer with the North Carolina Department of Transportation in Raleigh.
A compilation of Henn’s videos has been viewed more than 4 million times on YouTube. Henn hopes the attention could prevent the all-too-common sight of large vehicles hitting the structure. The video shows the top of trucks, busses and RVs having their trailer roofs sheared off.
"I think a lot of the drivers are distracted — there's a lot going on on this stretch," Henn said. "You've got several traffic lights, it’s a fairly narrow part of the road, so if you have dense traffic, you're looking at the traffic and not so much at the sign."
"There's all kinds of excuses, but the bottom line is really they're not paying attention," he said.
Gabe Gutierrez is an NBC News Correspondent based in New York. He reports for all platforms of NBC News, including "TODAY," “NBC Nightly News," MSNBC and NBCNews.com.