The effect of copper naphthenate treatment on electrical resistance of Douglas-fir utility poles was compared with similar
poles either left untreated or treated with pentachlorophenol (penta). Penta-treated and untreated wood had similar electrical
resistance shortly after treatment and after a 3-month outdoor weathering period. Electrical resistance of copper naphthenate–
treated wood was more variable but consistently greater, indicating that poles treated with this chemical would not pose an
increased risk to utility personnel working on them
