CARBON FIBER STUDY EXECUTIVE SUMMARY Carbon fibers were produced nearly a century ago in the search for an incandescent lamp filament. During the 1950's and 1960's, experimentation resulted in stronger fibers and the use of their special strength properties in new materials called composites. These materials, which are composed of carbon or graphite fibers (the difference being the temperature of pyrolysis during manufacture) embedded in a resin binder, have opened a wealth of new structural engineering and consumer product opportunities. In the next decade, composites may become as important to the United States economy as the steel and aluminum they replace. No other materials now in prospect offer equivalent advantages. The potential benefits of composites are manifold. Higher strength, lighter weight military and commercial products portend energy savings and increased safety. Unfortunately, these benefits are not realized without risk. The carbon (or graphite) fibers used in the present generation of composite materials are finer than human hair, extremely good electrical conductors, and virtually indestructable. They are so light that millions are contained in a gram mass. If released into the air, they can easily be transported by winds or currents. In contact with electrical devices, they can create resistive loading, short circuits, and arcing, resulting in stoppages or destruction. A variety of actual incidents can be cited supporting the hazards the fibers pose to electrical equipment. Their health impact is not fully known and requires careful research and analysis before any firm conclusions can be reached. But at current manufactured diameters and lengths, based upon currently available information, they are primarily an irritant to the eyes and skin, like fiberglass, rather than carcinogenic or destructive to lung tissue. In July 1977, the Director of the Office of Science and Technology Policy was directed by the President to conduct a study of graphite composite materials analyzing the potential problems and providing a plan for possible Federal action. The study revealed that current uses of carbon/graphite fibers worldwide entail about 700,000 pounds of material. At least six countries are currently producing composites and fabricating them into products. Major uses today are in military and commercial aircraft, with a growing list of consumer products, e.g., skis, fishing rods, golf clubs, etc. The major anticipated use is in automobiles where weight reductions necessary to realize fuel economies can only be achieved by replacing steel and aluminum with composite materials. Worldwide use, by 1990, could reach one billion pounds. Inadvertent fiber release, during manufacture or by destruction of the resin binder in fire, is the major hazard associated with composites. Major manufacturers are aware of the unique problems associated with these materials and have successfully applied controls to avoid the in-plant problems. With the expected rapid growth in the use of these materials in aircraft and automobiles, however, vehicle accidents followed by fire could become a substantial possible source of fiber release. Further, the uncontrolled incineration of industrial waste and of discarded consumer products could create serious problems. In some cases, protection might be realized by seclusion of equipment through protective covering or air filtering. New generations of electrical and electronic equipment can be manufactured with added protection at relatively modest cost. Three courses of action are open to the Federal Government: (1) do nothing at this time, (2) support further investigation of effects and solutions, or (3) impose regulatory restraints on all or parts of the life cycle of composite materials. The study supports further investigation and coordinated action by a number of Federal departments and agencies with existing relevant responsibilities. |