OSHA requires construction employers to keep all equipment, materials, and workers at least 10 feet from any power line carrying up to 50 kilovolts (kV), with greater distances for higher voltages. Dedicated space: The space equal to the width and depth of electrical equipment in addition to the space extending from the floor to 6 feet above the equipment or structural ceiling. These rules, found in 29 CFR Part 1926 Subpart CC, apply primarily to crane and derrick operations. Certain high voltage equipment is enclosed within a “ High Voltage Cage,” a completely gated or walled space secured with a specialized lock, housing high voltage exposed conductors that do not adhere to typical safety clearances. Height: Extends from the floor/platform to at least 6. 5 feet (2 meters) or the height of the equipment. Understanding these dimensions is critical. The minimum approach distance chart defines safe working distances to prevent arc flash injuries. Based on NFPA 70E and OSHA standards, it helps protect electrical workers by specifying limits by voltage level.
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