The air discharge currents from two humans having different physique with a wide range of charging voltages from ±1 kV to ±15 kV are measured via an IEC specified electrode to reveal that a specific relationship holds between the peaks per kV and rise-times regardless of human physique, charging voltages, polarities and spark lengths, which is also shown by analyzing a simplified equivalent circuit for human air discharge based on the IEC standard. This derives the specification required for the first peak waveform of the contact discharge method.