Aug. 21, 2007 -- There weren't any carbon monoxide detectors in the apartment complex where five Virginia Tech students were badly poisoned Sunday. They lived in an apartment building off campus, where there are no laws mandating carbon monoxide detectors.
Only 10 states have laws mandating carbon monoxide detectors in at least some residential buildings — Virginia is not one of them, despite the staggering statistics. Carbon monoxide kills more than 500 people a year in the United States.
But even with detectors, carbon monoxide can sometimes reach dangerous levels. Ross McGlaughlin, of ABC's Washington, D.C., affiliate WJLA, found it took 20 minutes for carbon monoxide detectors to sound after sensing fumes.
Experts recommend installing one detector, ranging in price from $20 to $50, in the hallway outside of every sleeping area in your home. Additionally, there's no substitute for good maintenance; all fuel-burning appliances should be checked yearly.
After Sunday's incident, one Virginia Tech mom bought carbon monoxide detectors for every apartment in the complex — something they could have used this weekend.
Virginia Tech student Britnye Kurty and her roommates said they felt nauseous and dizzy Sunday, so much so that they called the gas company.
"It was very, very scary," Kurty said.
That phone call may have saved the five women who lived just below them.
"And as soon as the technician from the gas company went in there, he started immediately calling for help," Kurty said.
The colorless, odorless carbon monoxide had been seeping into the apartment for hours.
Investigators suspect a faulty hot-water heater.
Doctors said the girls were very lucky because they had tremendous amounts of carbon monoxide in their bodies.
"These women had a peak level of somewhere [in] the 40 percent range. A normal person would have much less than 1 percent," said Dr. Bret Stolp of the Duke University Medical Center.
As the levels of carbon monoxide increase, so does the chance for difficulty breathing, and eventually, death, according to Dr. Christopher Holstege of the Blue Ridge Poison Center.
"We didn't have carbon monoxide detectors. We only had smoke detectors," Kurty said.