"I walk in every day to get those reports, and every day, let's just say the stress level increases because we have to get that taken care of," Muñoz told 13 Investigates during his first sit-down interview since being sworn in on Aug. 14.
Muñoz is taking over HFD at a time when response times are up and staffing shortages have resulted in not enough firefighters to operate crucial lifesaving equipment.
"Besides morale - that is my number one priority - is how do we increase the staffing," Muñoz said.
Marty Lancton, union president of the Houston Professional Fire Fighters Association, said every station citywide has an engine, but not every station has a ladder truck, which is crucial for searches and rescues.
"There's only usually one ladder truck for every three to four fire stations, and so if one ladder truck is out ... that means in that area, three or four territories away, all of that is going without having coverage, and you're having to call for a ladder truck that's even further away," Lancton told ABC13 in a recent interview before Muñoz took over.
13 Investigates found a ladder truck had to come from miles away during a May 12 fire at a duplex in the Acres Homes area despite a station just down the road.
Fire Station 67 was less than a mile down the street from a home on West Little York Road that officials say was set on fire by an arsonist.
But, while the engine from Station 67 responded, the ladder truck at that station did not respond due to staffing. Internal records show the ladder truck at Station 67 was out of service.
The closest available ladder truck was four miles away at Fire Station 31.
"Those are things that we have to really work on, and again, I say (it's) unacceptable," Muñoz said.
He said that on any given day, up to five trucks could be pulled out of service because there are not enough staff on duty to run them. This is one reason response times in the city are getting longer.
Last year, the fire department's average nighttime fire response time was seven minutes - up from six minutes and 23 seconds in 2018. The nighttime EMS response for HFD went from seven minutes and 16 seconds in 2018 to 11 minutes and 32 seconds last year.
According to data provided by HFD, the number of incidents to which both fire and EMS responded also increased over the last five years.
"It's not acceptable," Muñoz said. "The residents of Houston should have that expectation that every fire station is going to have that equipment staffed to be able to respond."
As of last month, HFD has 588 unfilled and open positions, so firefighters are being called in to work extra shifts.
"That is a big problem when it comes to the emergency response business. If you don't have units in service and you don't have enough units in service to respond, that puts life safety at risk," Lancton told 13 in a recent interview before Muñoz took over. "We see a light at the end of the tunnel. We see a mayor that has focused on Houston Fire Department and rebuilding a world class fire department, but in order to build that back up, it takes time."
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For months before Muñoz took over, 13 Investigates asked his predecessor, former fire chief Samuel Peña, for an interview about the increase in response times and staffing shortage.
ABC13 never got to interview Peña.
However, 13 Investigates asked Muñoz if response times would get lower under his leadership.
"Yes, they are," Muñoz said. "That's a promise."
He said his short-term goal is to implement an aggressive HR plan and hire 300 firefighters by the end of the fiscal year in July 2025. He said it helps that staff told him they've heard from about 100 former HFD firefighters looking to rejoin the department under its new leadership and contract.
"My number one priority is making sure the firefighters have what they need, that this fire department has the staffing that is needed to provide that response for the residents of Houston that is expected," Muñoz said.
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