Do you live in an area with high humidity? This green effect is simply oxidization of the brass prongs. You may want to keep them shiny with a little bit of Scotchbrite tm.. Possibly, dissimilar metals in your wall plugs contacts are causing this slight corrosion. You really should only worry if the vac's plug is getting hot or very warm.
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Do you live in an area with high humidity? This green effect is simply oxidization of the brass prongs. You may want to keep them shiny with a little bit of Scotchbrite tm.. Possibly, dissimilar metals in your wall plugs contacts are causing this slight corrosion. You really should only worry if the vac's plug is getting hot or very warm.