After every fatal fire in Baltimore, including a blaze that took the lives of three children Friday, fire officials remind neighbors of the importance of smoke alarms.
Since their introduction in the 1970s, the devices have saved thousands of lives. But a growing number of experts now say that the best-selling and least-expensive smoke alarms in U.S. homes react so slowly to certain smoldering fires that the devices can go off too late for occupants to escape with their lives.
Critics say these "ionization" alarms are also too quick to sense cooking smoke, so their owners are two to six times more likely to disable them. Removing the batteries to silence these "nuisance" alarms leaves residents with no working alarm.
"Every night before I fall asleep I say a prayer for the two or three people I know are going to die that night because they have the wrong smoke detector," said Deputy Chief Joseph M. Fleming of the Boston Fire Department.
Fleming is an outspoken advocate for alarms that use an alternative "photoelectric" technology to sense smoke. Photoelectrics cost slightly more, he said, but they're quicker to sense smoldering fires and less prone to nuisance alarms. Although ionization alarms are faster at detecting flaming fires, he said, the advantage is a small one.
Maryland fire safety officials acknowledge the advantages and disadvantages of each technology. But they're reluctant to say anything that might discourage people from installing and maintaining any alarm.
"Far more people perish because they don't have any smoke detectors" than because they have the wrong kind, said Capt. Raymond C. O'Brocki, head of Baltimore's Fire Prevention Bureau. "It's not a question of good and bad. It's good, better and best."
Boston's Fleming does not hesitate to criticize. He suspects that tardy or disabled ionization alarms might have been a factor in up to a quarter of the fire deaths in Massachusetts - and might explain why some victims die even when alarms are present.
Investigators have not determined what started Friday's fire on Springdale Avenue or whether the smoke alarm they found had gone off.
After an electrical fire in December that killed two Roland Park children, they were similarly uncertain. Last summer, three young people died when a vacation home near Easton caught fire. By the time alarms sounded at 2 a.m., survivors said, the house was full of smoke and flames.
