Respiratory hazard from removal of ceramic fiber insulation from high temperature industrial furnaces.
Ceramic fiber insulation is being used increasingly as a refractory lining for heat treating and preheating furnaces in the iron and steel industry. This is largely due to its superior thermal resistance per unit thickness when compared to insulating fire brick, which was the previous mainstay of refractory linings. Although toxicity data to date have found these ceramic fibers to be innocuous, recent studies have shown the fibers to devitrify and undergo partial conversion to cristobalite when exposed to elevated temperatures. This paper presents the exposure hazards to cristobalite found during the removal of various brands of ceramic fiber insulation from heat treat furnaces and the extent of fiber transformation to cristobalite.
D002516:Ceramics / Q000009:adverse effects*; D004391:Dust / Q000009:adverse effects*; D006361:Heating / Q000295:instrumentation*; D006801:Humans; D008452:Maximum Allowable Concentration; D010316:Particle Size; D012822:Silicon Dioxide / Q000009:adverse effects*; D012829:Silicosis / Q000209:etiology*
D004391:Dust; D012822:Silicon Dioxide