ISO 148-2:2008 covers the verification of the constructional elements of pendulum-type impact testing machines. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out, for instance, in accordance with ISO 148-1. It can analogously be applied to pendulum impact testing machines of various capacities and of different design. Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance with ISO 148-2:2008 are referred to as industrial machines. Those with more stringent requirements are referred to as reference machines. Specifications for the verification of reference machines are found in ISO 148-3. ISO 148-2:2008 describes two methods of verification: a direct method and an indirect method.