In the first edition of the IEC61000-4-5 (1995), the 10/700 uS pulse (this is the open circuit voltage waveform) had no specifications for its short circuit waveform.  The second edition (2005) specifies 5/320 uS as the short circuit current waveform.  The 10/700 uS pulse is also referred to as a combination waveform in the second or later edition of the standard.