This International Standard specifies two dissolution methods for the determination of the resin, reinforcement-fibre and mineral-filler contents of moulding compounds and prepregs: Method A: Extraction by Soxhlet. In cases of dispute, this method is the reference method. Method B: Extraction by immersion in solvent in a beaker. This method uses simpler equipment, making it suitable for quality assurance testing. This International Standard is applicable to the following types of material: — prepregs made from yarns, rovings, tapes and fabrics; — SMC, BMC and DMC moulding compounds. Typically, reinforcement fibres are coated with sizing or finishes. These normally dissolve with the resin and are, therefore, included in the resin content. This International Standard is not applicable to the following types of reinforced plastic: — those containing reinforcements which are soluble (or partly soluble) in the solvents used to dissolve the resin; — those in which the resin is partly or fully cured and so not fully soluble in organic solvents. NOTE — ISO 1172:1996, Textile-glass-reinforced plastics — Prepregs, moulding compounds and laminates — Determination of the textile-glass and mineral-filler content — Calcination methods, may be used where the resin is cured.