30 CFR § 77.509 Mandatory Safety Standards, Surface Coal Mines and Surface Work Areas of Underground Coal Mines

§ 77.509 Transformers; installation and guarding.

Current through Jul 27, 2026 · Read all of Part 77

(a) Transformers shall be of the totally enclosed type, or shall be placed at least 8 feet above the ground, or installed in a transformer house, or surrounded by a substantial fence at least 6 feet high and at least 3 feet from any energized parts, casings, or wiring.

(b) Transformer stations shall be enclosed to prevent persons from unintentionally or inadvertently contacting energized parts.

(c) Transformer enclosures shall be kept locked against unauthorized entry.

← § 77.508-1 Lightning arresters; wires entering buildings.§ 77.510 Resistors; location and guarding. →