Sometimes it happens even below the arc breakdown voltage via air... Air molecules are slightly less dense along the surface of a smooth flat surface due to molecular 'bounce', so electrons creep along the lower density of a surface.
Hence, creepage on a PCB.
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Sometimes it happens even below the arc breakdown voltage via air... Air molecules are slightly less dense along the surface of a smooth flat surface due to molecular 'bounce', so electrons creep along the lower density of a surface.
Hence, creepage on a PCB.