"If tomorrow that call came in, I'm going in," he said. "This is what comes with the job."
But now the 52-year-old's main job is taking care of himself.
"I got 20 years — there are guys that didn't make it out that day," Kevan said. "I'm on borrowed time."
Like many of his brothers, Kevan developed 9/11-related cancer. He was diagnosed with non-Hodgkin's lymphoma in 2019.
"I said to God, 'Please, I need more than 3 to 6 months to put my affairs in order,'" he said.
Countless rounds of chemotherapy and radiation and just last month a bone marrow transplant (donated by an anonymous 25-year-old man) have bought Brian more time to keep fighting.
"On 9/11, 343 of my guys didn't go home," Kevan said. "I don't think another family member of the 343 can hear another 9/11 guy died."
Kevan's doctor told him he won't be in the clear for at least two years after the bone marrow transplant. So until 2023, he is taking it day by day, praying for the best.
"Every little ache or pain in your mind, you wonder if something is coming back," he said.
He has a compromised immune system as it is and staying safe during the coronavirus pandemic is a priority.
"Every time you talk to someone either they have COVID or someone in their family has COVID," he said. "It's like my world gets smaller and smaller."
But Kevan is holding onto big dreams for a full recovery, vowing to live each day as it comes.