This part of ISO 29582 describes a method of determining the heat of hydration of cements by means of solution calorimetry, also known as the solution method. The heat of hydration is expressed in joules per gram of cement. This part of ISO 29582 is applicable to cements and hydraulic binders, whatever their chemical composition. NOTE 1 Another procedure, called the semi-adiabatic method, is described in ISO 29582-2. Either procedure can be used independently. NOTE 2 It has been demonstrated that the best correlation between the two methods is obtained at 7 d for the solution method in this part of ISO 29582 compared with 41 h for the semi-adiabatic method in ISO 29582-2.