National Electrical Installation Standards

Standards as High as Your Own

Friday, February 9, 2018


Is an inhibitor required to be used on aluminum conductors?

Darryl Vickers



Hey Darryl thanks for your question. The NEC does not require that corrosion inhibitors or anti-oxidant compounds be used as a general rule, even though it is a common practice. Electrical connections must comply with 110.14 and inhibitors and compounds, if used, must be suitable for the use as stated in the third sentence. If manufacturers of listed equipment provide or specify a corrosion prevention method it must be used as stated in 110.3(B). Battery connections made with dissimilar metals must use an antioxidant material if recommended by the battery manufacturer as stated in 480.4 and 706.31.


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