It's present, to some degree, in almost every American home. Now, fire safety and health officials are increasingly questioning its use.
It's PVC, or polyvinylchloride, and it's been used for 35 years in everything from telephones to automobile bumpers to wallpaper. Inexpensive, lightweight, and versatile, in the last decade it has overtaken steel as the chief ingredient in drains, vents, and underground pipes. The use of some PVC products grew from 30 percent in 1972 to 46 percent in 1980.
But the glamour appears to be wearing off:
* Statewide public hearings were held recently in New Mexico by construction industries to determine whether to ban certain PVC products from the state's electrical code.
* The New York Transit Authority decided last month against further use of PVC electrical tubing in subway stations after health officials warned of the danger posed by burning plastic.
* The Chicago City Council decided against including PVC in the city building code as electrical conduit after testimony by toxicologists.
As PVC's use has grown so have questions about its safety. Fire-safety experts say that the large quantity of plastics, including PVC, in several major fires - the MGM Grand Hotel in Las Vegas, the Stouffer's Inn in Harrison, N.Y., and the Beverly Hills Supper Club in Southgate, Ky. contributed to the spread of the fire and to the injuries and deaths. One toxicologist says PVC burns hotter and faster than wood, and produces smoke 20 times as toxic. PVC can smolder for hours at temperatures too low to trigger certain fire detectors, releasing toxic fumes, says Gordon Vickery, director of the Foundation for Fire Safety in Arlington, Va.
Fire-safety officials express concern at the use of PVC in places where fast exits aren't always possible: prisons, high-rises, nursing homes, airplanes, and subways.
Spokesmen for two PVC manufacturers, B.F. Goodrich and Carlon, claim that steel manufacturers have fueled the uproar over the plastic. The spokesmen say steel firms don't want to lose their once-exclusive conduit and tubing markets. A steel industry spokesman denies that steel companies advocate removing all plastics.
Plastics manufacturers assert that PVC is not the only building material that releases toxic fumes when burned. Michael O'Mara, vice-president of research and development at B.F. Goodrich, claims that ''although PVC does release toxic combustion products when it burns, so do other materials. And PVC is no worse.''
Several of the major fires, he says, can be attributed to fire-code violations, rather than PVC. In the MGM Grand fire, for example, there was a lack of sprinklers and fire-resistant barriers, according to the National Fire Protection Association (NFPA).
Plastics and steel manufacturers alike call for stricter adherence to fire codes and more testing. One problem: Duplicating actual fire conditions in a laboratory is difficult - there is no way of determining how different elements react with one another, says Rosalind Anderson, of Arthur D. Little Inc., a Boston research firm.
Although the plastics industry and independent labs have conducted toxicity and flammability tests on PVC for the last 10 years, a national test standard has yet to be established that would utilize this research and control the application of PVC. That is changing. The NFPA is examining the toxicity issue and plans to discuss it, for the first time, at this year's annual meeting. The National Bureau of Standards has developed a test for toxicity, which it is now in the process of approving.