Christina Huff had never paid much attention to the carbon monoxide detectors her mother bought for her new condo until the beeping wouldn't stop early Thursday morning.
It was around 4 a.m. when Huff was jolted awake in her third-story bedroom at Cordoba & Beach Park Condos, located off Kennedy Boulevard near WestShore Plaza. She didn't smell anything and didn't feel sick. Her tiny, mixed-breed dog, Rafiki, seemed fine. Still, she had a gnawing feeling that something was wrong, she said. She called Tampa Fire Rescue's non-emergency line.
"It could totally be just a false alarm but both of them are going off, which was weird," Huff, 23, told the dispatcher. "Do you think they could come without any sirens or anything?"
That split-second decision saved three neighbors' lives.
One neighbor in the six-unit building, Emily Sealy, had accidently left her 2015 Volkswagen sedan running in her enclosed garage while she slept two stories above it. It has a push-button start and continued running without the keys inside, filling adjoining units with high levels of poisonous carbon monoxide.
When firefighters and Tampa police began evacuating residents, breaking in doors of three condos where no one responded, they found Sealy, 32, and her small dog, George, both unresponsive.
Firefighters performed life-saving measures and administered oxygen to both while neighbors watched. George recovered and was given to Sealy's father, who had been called to the apartment. Sealy was taken to Tampa General Hospital and was released Friday.
"A firefighter had to carry her out over his shoulder,'" said Cordoba resident Bailey Muchler, 19, who was awakened by the commotion. "They put her on a stretcher and they pulled a sheet over her and we were all like, 'Please, please don't let her be dead.' It's so freaky that this could happen so easily."
A Florida statute requires all new construction permitted since July 2008 to have a carbon monoxide alarm installed within 10 feet of each bedroom if the structure contains a fossil fuel-burning appliance, a fireplace or an attached garage.
The Cordoba & Beach Park condos were built in 2004.
But Huff grew up in Chicago, where gas appliances are common. At home, carbon monoxide detectors were always built into fire alarms, she said. When she moved out on her own, her mother insisted that she buy one for each floor of her condo.
"They've never gone off by themselves; I kept taking the batteries out and taking them outside for a little bit to see if they would stop," Huff said. "If there was gas in the apartment, I honestly didn't think it could affect anyone else. I didn't realize how all of us are attached."
Officials are not sure how long Sealy's car was left running, but it took about two hours to ventilate the apartments, Huff said.
Exposure to extremely high concentrations of carbon monoxide can kill you in 15 minutes, said Dr. Alfred Aleguas, managing director of the Florida Poison Information Center of Tampa at Tampa General Hospital.
Carbon monoxide is an odorless, tasteless, colorless chemical that prevents molecules in the blood from absorbing oxygen, he said. Exposure to carbon monoxide in the air means that most people are used to carbon monoxide concentrations of 1 or 2 percent, he said, and smokers to concentrations of 8 or 10 percent. At that level, some may experience a low-level headache, and at 20 percent it's common to experience nausea and vomiting, he said. At 30 percent or higher, the heart and brain begin to shut down and there can be lasting effects, such as memory loss or seizures, that can take months or even years to clear. Any concentration above 50 percent is potentially lethal.
The only treatment for carbon monoxide poisoning is pure oxygen, he said.
"People don't realize how quickly carbon monoxide can build up when you run a car or a generator in a closed garage," Aleguas said. "People have died just from running a hibachi grill in a tent while camping to keep warm."
In 2011, a 23-year-old woman died in her apartment at the Vista Grande at Tampa Palms after a neighbor left his car running in a garage adjacent to her bedroom for about 11 hours. Last year, two East Bay High School students died while sitting in an SUV with the engine running in a closed garage. Their deaths were accidental, officials said.
When Huff's neighbor Dale Nabors, 57, returned to his condo Thursday, he immediately checked his new smoke alarms to make sure they came with a built-in carbon monoxide detector, he said. Standing outside with his neighbors Thursday morning was a "wake-up call" in more ways than one, he said.
On any given night, Cordoba's immaculately kept Mediterranean courtyards will typically be empty. Neighbors in the quiet, upscale neighborhood tend to keep to themselves. Nabors has lived there for five years, but didn't know his neighbors' names. Neither did Huff, who has lived in her condo for about eight months.
"We all kind of talked to each other for the first time and said it probably isn't good that we don't know each other and got each other's phone numbers," Nabors said. "It makes you think about being prepared and looking out for the people around you."
Times researcher John Martin contributed to this report. Contact Anastasia Dawson at firstname.lastname@example.org or (813)226-3377. Follow @adawsonwrites.