This document specifies a method for the determination of the gross heat of combustion (QPCS) of products at constant volume in a bomb calorimeter. This method is intended to be applied to solid products. NOTE Liquids can be tested with similar equipment and using conditions described in ASTM D240[1], as described in IEC 61039[2] using ISO 1928[3] test equipment. Annex A specifies the calculation of the net heat of combustion, QPCI, when required. Information on the precision of the test method is given in Annex B.