We're back at 7:41, with "Gma" investigates. Smoke detectors this time. Turns out not all smoke alarms are created equal. There can be dramatic differences in how well they work, depending on the type... See More
We're back at 7:41, with "Gma" investigates. Smoke detectors this time. Turns out not all smoke alarms are created equal. There can be dramatic differences in how well they work, depending on the type of fire. We investigated the response time to some smoke alarms. ABC's gio Benitez has that story for us. Reporter: "Gma" investigates conducted two demonstrations. Let's go. Reporter: Showing response times to smoke alarms in very real fire scenarios. It's getting smoky in there. When buying a smoke alarm, you may not know there's two types on the market. Ionization, and photoelectric, which are quicker in detecting smoldering fires. 90% of homes have only ionization alarms. Doug believes he paid the ultimate price. He lost his daughter, Julie, a senior at Miami university of Ohio in a house fire in 2005. 11 students were sleeping when a smoldering fire broke out. Eight survived. There were 17 ionization smoke detectors in the house. It's not like the landlord didn't care about fire safety. He had no idea there was a difference. Reporter: We asked the northeastern Ohio fire prevention convention to conduct a demonstration, buying six leading alarms from six manufacturers. Two ionization, two photoelectric. And mounted the alarms in a hallway of this house, slated for demolition. There were nine cameras to capture all angles. First, a fast blazing fire. The ionization went off after 45 seconds. And the photoelectrics after four and five minutes. Four just activated. Reporter: Watch what happens in a smoldering fire. Starting ignition. Reporter: Right now, Mike is setting the smoldering fire. We start our timer at the first sight of smoke. Activation at the 12:15 mark. We have photoelectric one. Reporter: A minute and a half later, another alarm. Another activation. Photoelectric number four. Visibility is good. And I would be able to make it out. Reporter: The minutes tick by. At 22 minutes, the first dual alarm goes off. At 49, the second. But no ionization alarms. Mike, it's getting hard to see you, man. Conditions in here are worsening. Reporter: I can't see you on the wide shot. Visibility is minimal. And the conditions are now life-threatening. We have to get you out of that environment now. Reporter: After 1:10, the fire chief deems the house unsafe for the firefighters. If you were in that smoke, you wouldn't survive very long. Reporter: A government study in 2004 found similar results. Photoelectrics 30 minutes before ionizations. Two of the biggest alarm manufacturers told us their alarms meet industry standards. But for optimal protection, recommend consumers use both types of alarms. And that's the key. Now, the consumer products safety commission says it is actively working to improve the safety standards so that both alarms, here they are right here, that they work faster and better in both types of fires. And check that expiration date. A lot of people don't know that. They have an expiration date. I'm going to be checking mine. I didn't know there were two detectors. You'll know by looking at the package. Thanks very much for that.
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