Jeremy Paniagua's mother died saving his life after a fire broke out in their two-bedroom apartment in East Harlem in February 2005. His mother, Jeanette Montanez, threw her 11-year-old son into a bathtub and covered him with her body to protect him from the flames. Her silhouette was burned onto the flesh of his back by the intense heat and flames.

"His back is burned pretty badly, but you can see the patch where she held him, where she put her head between his shoulder blades and where she held onto his right arm," says Mallory Claudio, Jeremy's older sister, who was pulled out of the 112th Street apartment by firefighters.

Investigators later determined the fire that killed Montanez was started by a cigarette. And while there was a working smoke detector in the apartment, it may have failed to give the kind of advanced warning that allows people to flee fires with their lives, and without scarring burns.

Two types of protection

Approximately 96 percent of American households have at least one smoke alarm, the vast majority of which are traditional ionization smoke detectors. These use tiny amounts of radioactive material to detect fine smoke particles, the type generated by hot fires with high flames most commonly started by cooking accidents or improperly tended candles.

But a growing number of experts are lobbying for a shift toward photoelectric smoke detectors, which are faster at detecting the larger smoke particles that are generated by smoldering fires, like those caused by smoking accidents or slow-developing electrical fires. Photoelectric sensors shoot beams of light into a chamber that are not aimed at a sensor, but deflected toward the sensor by smoke particles.

In May of 2012, five New York City Councilmembers proposed a law to require photoelectric smoke detectors in residential buildings. Councilwoman Elizabeth Crowley, who chairs the Fire and Public Safety Committee, was the prime sponsor of the proposal.

"We know that the photoelectrics are better at alerting people to the fires that are killing more people," says Crowley. "A lot of people die from smoke inhalation and not raging fires. The traditional smoke alarms go off frequently when people are cooking or showering and they disable them and forget to reconnect them."

Although fires caused by smoking accounted for only 5 percent of structure fires in the United States between 2006 and 2010, they were responsible for the highest percentage of fatalities (24 percent), followed by fires involving heating equipment (20 percent) and cooking equipment (15 percent). According to some researchers many of the smoking-related deaths could have been prevented if the structures they occurred in had been required to have the slightly more expensive photoelectric smoke detectors, which most building codes do not now require.

Marshal's crusade

The fire that killed Montanez occurred in the New York City Housing Authority's Johnson Houses development. Claudio, who was 18 at the time of the blaze, later found out that the New York City Housing Authority, like nearly all landlords, used the less expensive ionization smoke detectors. (NYCHA declined to comment, citing the pending legislation.)

Claudio learned that the fire she survived involved an ionization smoke detector through the dogged persistence of a man named Jay Fleming. A deputy fire chief from Boston, Fleming's obsession with photoelectric smoke detectors began after a 1990 fire—started by a cigarette—killed five members of a Boston family, including three children ages 3, 2 and 10 months.

Fleming, who has a master's degree in engineering, researched the issue and began applying pressure to push for legislative change. He routinely reaches out to survivors and relatives of fire victims and tries to enlist their aid to pressure municipalities to change their laws and building codes.

"There are tons of studies that conclude that an ionization smoke detector will not give you enough time to get out of the house in a smoldering fire," says Fleming, who managed to get the Massachusetts state legislature to require photoelectric detectors in his home state. "I believe that somewhere between 10,000 and 15,000 people have died unnecessarily over the past 20 years because they didn't have adequate information about their smoke detectors."

Fleming says he only uses photoelectric detectors in his home because hot, fast moving fires—the ones that ionization detectors are best able to detect—frequently occur from cooking accidents while people are awake and able to either put the fire out or get out of the building. He's more worried about smoldering fires, which begin quietly and can disable or kill with subtle smoke, and which ionization detectors are slower to detect.

Claudio says that the night her mother died, she was awakened by the ionization detector, but by the time she woke up, the two-bedroom apartment was so filled with smoke she could barely see or breathe. "All I saw was thick black smoke and some sparks," she says. "I ran to the window by the air conditioner and just stayed there, it was the only place there was any air. That's where the firemen found me and took me out."

Codes don't differentiate

The city's building code specifies where smoke detectors must be located and how they are to be connected to one another and to fire dispatch systems, but is silent on what type of detector to use. Same with the separate New York City Fire Code.

The New York City Fire Department, the National Fire Protection Association (NFPA) and several other agencies recommend installing both types of smoke detectors, but have only begun making the recommendation within the past few years and have stopped short of pushing for requiring photoelectric devices.

Fleming maintains that most of the time the smoke detector industry sponsors free smoke alarm giveaways, they donate ionization models. Heather Caldwell, a spokeswoman for Kidde, the world's largest manufacturer of fire safety products, would not provide specific numbers about her company's donation policy.