Refractory ceramic fiber (RCF) is an energy-efficient, high-temperature ins
ulation, used principally in industrial furnaces, heaters, and reactors. Pr
ior to the 1980s, there were few publications dealing with the potential he
alth effects of this material. However, with the advent of higher energy co
sts and the need for thermally efficient high-temperature insulating materi
als, production of RCF grew rapidly, as did interest in its potential healt
h effects. This article provides a comprehensive and integrated review of t
he toxicology (in vitro and in vivo), epidemiology, and risk analysis liter
ature of RCF. Based on the available literature, we conclude that an occupa
tional exposure of 0.5 fibers per cubic centimeter (cm(3)) [8-h time-weight
ed average (8-h TWA)] results in an occupational health risk no greater tha
n 9.1 x 10(-5).