A RESEARCH scientist at the National Bureau of Standards (NBS) says the use of polyurethane foam to stuff America's upholstered furniture can constitute a fire hazard and may need to be curtailed.
"There's no quetion," said Vytenis Babrauskas of the bureau's Center for Fire Research, "that if we could wave a magic wand and get rid of all polyurethane, we'd be better off."
In August the bureau published a report by Babraukas detailing his studies of polyurethane's performance when subjected to open flames. He found the material prone to rapid flare-up and intense heat. In at least one test case, the material led to a fire that could completely engulf a room within minutes.
"One polyurethane sofa in your living room may not be a hazard," he said in a recent interview. "but put a sofa, two chairs and an ottoman all made of polyurethane together, light them, and what you have is a holy inferno."
The report joins a growing body of scientific evidence documenting the hazards of polyurethane, a man-made plastic that in the last 20 years has become the most widely used stuffing material for upholstered furniture. Babrauskas summarized some of the evidence in his report.
Tests on upholstered furniture in 1972 showed that flames spread two to three times faster in furniture pieces made with polyurethane than in those made with cotton padding.
In 1974, the Southwest Reseach Institute conducted a series of tests, sponsored by the Society of the Plastics Industry, on mattresses and upholstered furniture. "The results showed cotton batting specimens burning slowest," said Babrauskas, "and latex foam specimens developing fastest fires, with polyurethane foam being slightly slower than latex."
Scientists at the Swedish Defense Agency tested furniture pieces with cotton stuffing and others with polyurethane in 1974 and 1975. "Since a non-flaming radiant ignition source was used, the cotton batting furniture achieved flaming ignition in 34 to 120 minutes, while the polyurethane specimens ignited in less than one minute," Babrauskas said.
Further tests were performed at the Southwest Research Institute in 1976: "The plastic-furnished room," Babrauskas said, "showed a faster developing and more severe fire [than that furnished with cotton upholstered furniture]."
A series of tests at the British Fire Research Station in 1974-76 revealed, he said, that some of the furniture pieces stuffed with foams burned so fast the wooden frames didn't have a chance to ignite before the fire was out.
One of Babrauskas' conclusions, that furniture should use less urethane and fewer thermoplastic fabric materials, seems to fly in the face of nearly eight years of bureau testing at the behest of the Consumer Product Safety Commission.
To date the commission's efforts to reduce home fires have centered on a proposed mandatory standard that would require upholstered furniture resist smoldering cigarettes. (In November the commission agreed to monitor for a year of voluntary program developed by the furniture industry.) Such fires number more than 30,000 annually, kill approximately 500 persons, injure more than 1,700 and result in property damages exceeding $40 million.
Tests conducted by the NBS and other laboratories across the country suggest the simplest means of preventing smoldering fires would be to stop using many cellulosic fabrics (cotton, rayons and linens) in favor of thermoplastic ones (nylons, polyesters and olefins).
They also encourage the use of polyurethane, which is far more resistant to cigarettes than cotton.
Babrauskas wrote, however: "A separate study of flaming ignition behavior is necessary, since flaming ignition and cigarette ignition behavior are not correlated -- good performance in one case does not necessarily imply good performance for the other."
The director of NBS' Center for Fire Research, Frederick B. Clarke, said the reason efforts to control residential fires have centered on making furniture resistant to smoldering cigarettes, rather than open flames, can be found in statistics.
Of the nation's fire deaths, 27 percent or more than 2,000, occur in private residences where furnishings (including mattresses) are ignited by smoldering cigarettes, making cigarettes the leading cause of fire fatalities. Ranking second, but resulting in only five percent of all deaths, are fires that begin in furnishings exposed to open flames.
"Our primary concern in writing the [cigarette] standard," said Clarke, "was the greatest cause of deaths."
Now, however, NBS officials are concerned that although the number of deaths directly attributable to open flame furniture fires may be relatively low, insidious qualities of polyurethane may contribute in other ways to fatalities, injuries and property damage. These qualities cannot be identified in fire statistics.
"There is so little known in the area," said Clarke, "we are devoting considerable time to finding out more."
Clarke's team is only beginning to understand the mechanisms that cause fires to spread and the conditions that make some fires more dangerous than others.
One fire phenomenon under study is the so-called "flashover," that moment when a fire ceases to be confined to one area and suddenly engulfs an entire room. In one of Babrauskas' tests, a polyurethane slab chair led directly to room flashover. Tests at the Swedish Defense Agency showed the maximum distance at which an armchair stuffed with cotton batting would ignite another object was 0.15 meters (about six inches). A burning polyurethane sofa lit objects as far away as 1.2 meters (nearly four feet).
In their efforts to save lives, NBS officials increasingly are studying home improvements that will allow people more time to escape fires. The initial findings are that filling your house with polyurethane isn't one of them.