BRYAN- They're supposed to save lives, but not all smoke detectors are the same.
"We believe you need the fastest possible warning you can get in a fire," said B. Don Russell, Ph.D. at Texas A&M University.
"We found that some of the most common smoke detectors sold in the United States actually don't work very well," Russell said.
Russell is a Distinguished Professor with the Texas A&M Department of Electrical and Computer Engineering.
He's studied smoke detectors for nearly 20 years and said certain ones can be deadly.
"You can have a very substantial problem and smoke detectors may not go off."
A simple aquarium test shows how long it takes for an isotonic smoke detector to alert a family of a fire.
"You will have a whole house full of smoke before this detector goes off," Russell said.
Every passing second is the difference between life and death.
"Some detectors go off so late in fires that often people cannot escape," Russell said.
Russell says he's investigated hundreds of fires where entire families died because they had the wrong smoke detectors.
"And they just didn't get a timely warning," Russell said of the families who passed away in the fires.
A photoelectric smoke detector could be the difference between life and death because it can detect the smoldering fires while isotonic detectors cannot.
The warning is impossible to ignore and he says it's something the public needs to take very seriously. "Have more than one smoke detector and make sure you have a photo electric smoke detector," Russell said.