Foam Alone

for Scientific American

Legislation on California state Sen. Mark Leno’s desk has the potential to affect every household in the U.S.

If Leno has his way, the state’s textile and furniture manufacturers, and thus probably all such makers in the U.S., will drastically alter the amount of flame retardant carried in almost every sofa, love seat and easy chair in the country.

At issue is something called Technical Bulletin 117 (or TB 117), an obscure California law enacted in the late 1970s. It requires all furniture stuffing foam in the state to withstand 12 full seconds of open flame, analogous to a cigarette lighter held against a couch with the upholstery ripped off. Furniture flammability is largely regulated by states, and California is by far the toughest.

“The biggest fuel load in your house is your polyurethane foam,” says Alex Morgan, a flammability expert at the University of Dayton in Ohio. “Polyurethane has a very high heat release rate so when it catches, you just have a very short period of time before you’re dead.”

The current law sets no requirements for how to keep products from burning during those critical 12 seconds, so furniture manufacturers turned to an array of chemical flame retardants mixed directly into the foam. Because these chemicals are cheap, and in order to avoid a separate production line to accommodate every state’s flame retardants threshold, major manufacturers now create all U.S. furniture foam to California standards.

Critics of these additives, however, worry they might be dangerous and want an alternative from the 12-second standard. It fails to prevent fires, they say—and worse, it allows dangerous chemicals to leach into humans and the environment.

Flame retardants in foam “are not effective enough to make them stop burning rapidly once they’re ignited. But they are effective in polluting the environment and creating health concerns,” says fire expert Vytenis Babrauskas, president of Fire Science & Technology, Inc., and a 16-year veteran of the National Institute of Standards and Technology (NIST). “You get the worst coming and going.”

Babrauskas specializes in the study of the temperature at which various household objects ignite and how fast they burn. He created several of the tools that the federal government uses to set standardsmeasure for furniture safety. He says that it takes very little flame retardant to stop a lit cigarette from igniting a couch and a phenomenal amount to slow a sizable flame—amounts often used in airplanes and prisons, according to his July 1988 special report for the National Bureau of Standards (NIST’s former name). He says, however, expecting home furnishing to withstand a smaller cigarette lighter flame for 12 seconds is arbitrary and demands too much of a chemical that may have adverse health effects.

The term “flame retardant” casts a wide net. Mostly it refers to organohalogens—compounds like DDT that incorporate halogens such as chlorine or bromine into organic molecules—that are naturally nearly nonexistent in mammals. Lately, attention has focused on one class of these, polybrominated diphenyl ethers (PBDEs), which tend to accumulate in living organisms and have been implicated in reduced fertility (for instance, in research published last year in Environmental Health Perspectives); decreased IQ (in research also published last year in the same journal); and for at least one PBDE that has since been phased out, cancer in rats. Another PBDE, pentabromodiphenyl ether (pentaPBDE), once the primary flame retardant in furniture, was voluntarily withdrawn by the chemical industry after a 2007 paper in Science showed a tendency to accumulate in the body.