Perfluorocarbons are known to react with silane because silane is a very strong reducing agent. However, quantitative information on their explosion limits are not known. So, in this study, flammability of silane/perfluorocarbon/nitrogen was examined experimentally. Their flammability areas were revealed quantitatively as triangular flammability diagrams, and the fact that perfluorocarbon reacts with silane was ascertained. (C) 2004 Elsevier Ltd. All rights reserved.