This standard specifies a test method for determining the reaction heat and reaction temperature of phenolic resins using a differential scanning calorimeter (DSC). The principle involves measuring the relationship between the heat flow or power difference between the sample and a reference material and the temperature under programmed temperature control using a differential scanning calorimeter. This yields an exothermic curve of the curing reaction, from which the reaction heat (typically expressed in joules per gram) and characteristic reaction temperature points such as the onset temperature, peak temperature, and end temperature can be calculated. This method generally requires the use of a differential scanning calorimeter capable of programmed heating and precise measurements.