NYPASS will hinder or slow down reactions between oil compounds and the copper surfaces in transformers and will thereby reduce the risk for formation of conducting compounds.

Addition of metal passivator is recommended by maintenance guide IEC 60422 edition 4. This mitigation technique has been used with good results against formation of potentially corrosive sulfur. Typically 100 mg/kg (0.01 % by weight) of this substance is added to inhibit the reactions of copper with corrosive sulfur.