What is the permitted minimum clearance between conductors for outside overhead spans not exceeding 300 volts?

The minimum clearance between conductors for outside overhead spans not exceeding 300 volts is established to ensure safety and prevent electrical hazards. In Washington State, as codified in the National Electrical Code and local regulations, the accepted standard for this clearance is 3 feet.

This spacing is critical because it helps to mitigate the risk of arcing or electrical contact between conductors, which can cause short circuits or equipment failures. Additionally, proper spacing accommodates thermal expansion, wind sway, and other environmental factors that can affect overhead lines.

The specific requirement of 3 feet is designed to provide sufficient distance to maintain safe operational conditions while also considering practical installation scenarios in residential and commercial settings. Therefore, this measurement is not merely arbitrary; it is based on years of industry understanding of electrical safety standards.