Safety Experts Question Effectiveness of Popular Smoke Alarms

By | July 24, 2006

When a jury this spring concluded a smoke alarm failed in a fatal upstate New York house fire, safety experts were already questioning whether popular models meet the threat posed by fast-burning synthetic materials now common in American homes.

The federal court jury found the design of popular “ionization” smoke alarms defective in the fire that trapped William Hackert Jr., 56, and his 31-year-old daughter Christine in their house near Albany in 2001. Survivors contended that First Alert and its manufacturing subsidiary BRK, which control 85 percent of the market, continued to make and sell millions of the cheaper ionization detectors despite knowing their disadvantages.

There are two common types of smoke alarms:

• Ionization alarms, which detect smoke with the help of radioactive material, sound earlier in fast-burning flaming fires.

• Photoelectric alarms, which detect changes in light patterns, sound earlier in slow smoky fires, which take time to transition to flames.

Under longtime national standards, either alarm is acceptable. Experts say both save lives, but the time needed to escape once flames start has gotten dangerously short, particularly for the disabled or impaired, because of fast-burning synthetics in furniture and carpets, and standards may need to change.

Consumer Reports in 2001 recommended that homeowners install at least one ionization and one photoelectric alarm on every level of a house to improve warning times for different types of fires. An April report from the Public/Private Fire Safety Council went further, noting that some test escape times were “tight or insufficient” with either alarm for bedroom or living room flaming fires. The group suggested that Underwriters Laboratories modify its standard to require faster detection of smoldering fires.

Current UL smoke alarm standards, first developed in the 1970s, require alarms to respond within 4 minutes of a flaming fire and in a smoldering fire before smoke obscures visibility by more than 10 percent per foot.

In today’s homes, the tendency for synthetics — like nylon and polyester in furnishings, fabrics and carpeting — is to smolder for a long time, then burn faster than natural materials like wood and cotton, which char as they burn. Synthetics melt and pool, then give off substantially more energy when they burn, said Tom Chapin, head of UL’s fire protection division.

That has shortened the time to “flashover” — from first flames to combustion of the entire room due to accumulated heat and gases — from an average of 12 to 14 minutes 30 years ago to about 2 to 4 minutes now, Chapin said.

“In the flaming scenario, the escape times are radically shorter,” he said.

The not-for-profit safety certification company in February began studying the smoke characteristics from 40 materials now commonly found in homes. Results are expected by the end of the year in the effort to make alarms more effective. Also under study are the byproducts of today’s smoke, which can be lethal.

“We change our standards because of changes in technology and changes in the way people use things,” said Chapin. He also pointed to an “unsettling” uptick in U.S. fire fatalities in the past 12 months to a rate of about 3,500 annually.

One likely factor is the increasing use of candles as mood lighting. They now cause about 18,000 fires a year, triple the number five years ago, Chapin said. A factor that helped cut fatalities is a drop in smoking.

The blaze that killed the Hackerts in the early morning of May 31, 2001, began with a frayed electrical cord behind the sofa that smoldered for some time.

“BRK had exclusive knowledge that sometimes in real world fires, sometimes these ionization detectors don’t go off at all,” said family attorney James Hacker.

The companies were ordered to pay widow Sheila Hackert $4.15 million in compensation and $500,000 in punitive damages.

The companies have filed motions for a new trial and to block the award. If that fails, they plan to appeal. Attorney James Heller said the family admitted disconnecting the batteries in some of their five smoke alarms, and he argued they had disconnected all of them.

“We were precluded by the judge from presenting evidence we believe would have convinced the jury,” he said.

The companies make and sell both ionization and more expensive photoelectric alarms. Heller says the packaging for years has said that for maximum protection, homes should have both, or else combination alarms, which BRK also makes.

Arthur Cote, executive vice president and chief engineer for the National Fire Protection Association, said 2004 data showed 96 percent of U.S. households had at least one smoke alarm. Civilian fire deaths dropped to 3,190 that year, down from 5,865 in 1977 when few homes had alarms.

About half the deaths still occur in the small percentage of homes without smoke alarms, Cote said. “Almost all of the time you find a ‘failure,’ the detector has been disabled,” he said.

At the trial, plaintiffs discovered 750 written complaints since the 1990s from customers who said their ionization detectors didn’t sound in actual fires, Hacker said.

First Alert requested all 750 smoke alarms back, almost half were sent, and they were tested, Heller said. “There were a small number of alarms that there were manufacturing issues or electrical issues, but the vast majority of them passed all the tests.”


On the Net:

Public/Private Fire Safety Council White Paper:

National Institute of Standards and Technology:

Underwriters Laboratories:

National Fire Protection Association:

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