1.1 This test method covers the determination of silica in RDF, RDF ash, fly ash, bottom ash, or slag. 1.2 The test method is an acid dehydration gravimetric procedure and is independent of interferences. This test method covers the determination of silica in refuse-derived fuel (RDF), RDF ash, fly ash, bottom ash, or slag. The test method is an acid dehydration gravimetric procedure and is independent of interferences. Silicon compounds shall be dissol