DENTON, Texas (CBSDFW.COM) –  Sujo John was at work on the 81st floor of the World Trade Center’s North Tower.

He heard the roar of an engine and the impact overhead.

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The wing of an airplane tore through his floor.

“I just remember hearing this incredible explosion,” he said. “I can still feel the heat, the smell of that day. Things burning around me…”

John and his coworkers rushed to the stairwell.

They were half way down, when they saw firefighters.

“We run out and these brave men run in,” he remembers thinking.

“They didn’t make it,” he said.

It’s something he thinks about often.

Pausing an interview, he glanced at the camera on his laptop.

“If you’re a fireman or policeman watching me right now, I just want to say, thank you,” he said, biting his lip to keep his emotions in check.

That hectic morning, on September 11th, 2001, his thoughts, though, were with his wife.

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She was four months pregnant and worked in the South Tower.

He heard the crash, as a second plane struck her building.

“Well, I was thinking the worst had happened,” he said.

It wasn’t until late that day Sujo learned she’d been running late to work.

She survived.

So, did their unborn baby, who today is an 18-year-old college freshman.

“It doesn’t feel like it’s 19 years,” he said.

Sujo John (credit: Sujo John)

The family now lives in Denton, but Sujo travelled to New York, as usual, this week to attend a memorial at Ground Zero.

His memory of 9/11 is still painful, still vivid.

“To be honest with you, I don’t think i want it to be erased,” he said.

Knowing others sacrificed their lives trying to save his has motivated him to make the most of whatever time has, help who he can, when he can.

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To find out more about his nonprofit helping end the human trafficking of women and children internationally, click here.