GB/T 16896.2 is the second part of the Chinese standard for digital recorders in high-voltage impulse tests and deals with the practical application of the instrument to impulse voltage measurement. Where the first part defines what the recorder must be capable of, this part defines what must be done with it. It specifies the recording window that must be used for a full lightning impulse and for a switching impulse, the number of samples that the record must contain, the way the base line and the waveform parameters are determined from the recorded data, and the smoothing and filtering operations that may be applied before the parameters are evaluated. It also addresses the evaluation of the virtual front time, the time to half value and the peak value from a digitised record, the treatment of superimposed oscillation on the waveform, and the way the uncertainty of the recorder combines with the uncertainty of the divider and the test circuit to give the overall uncertainty of the measurement.