How far from the floor can nonmetallic surface extensions run?

Nonmetallic surface extensions can run up to 4 inches from the floor due to industry standards and safety regulations that account for both accessibility and protection of the electrical components. This height allows for practical installation practices and ensures that nonmetallic extensions are positioned safely out of reach of potential hazards like spills, foot traffic, and other physical impacts that may occur at lower heights. Adhering to the 4-inch rule also helps in maintaining compliance with the National Electrical Code (NEC), which aims to establish consistent safety measures across electrical installations. This understanding is crucial for electricians, as it not only ensures compliance but also contributes to the longevity and safety of the electrical system.