In what specific situations do the 100kHz and 1MHz damped oscillation waveforms specified in IEC 61000-4-18 occur?

In what specific situations do the 100kHz and 1MHz damped oscillation waveforms specified in IEC 61000-4-18 occur?

Slow damped oscillation phenomena (100kHz) are seen in switching of outdoor power distribution equipment at high/medium voltage, and are predicted to occur in high-voltage busbar switching and industrial plants.
On the other hand, fast damped oscillation phenomena (1MHz) are predicted to occur in the operation of switchgear and control gear in wiring equipment of power networks.