scope:

This UFC provides safety requirements and guidance for anyone working on or near electrical components rated at 50 volts or above in facilities and related infrastructure. The scope includes electrical substations and switching stations, the associated distribution systems, and extending to electrical distribution systems inside facilities, including electrical equipment covered by UFC 3-501-01.

For the purposes of this UFC, low voltage is defined as 1,000 volts or less. Voltages higher than 1,000 volts are referred to as high voltage. Refer to the Glossary for definitions.

Note: The prior edition of this UFC designated 600 volts as the upper limit for low voltage because this voltage was considered the highest low voltage that would be typically encountered. The designation of 1,000 volts as low voltage has been chosen to be consistent with NFPA 70E and NFPA 70. However, NFPA 70E provides the same approach distances for voltages between 751 volts to 15 kV, and refers to voltage above 600 volts as medium voltage in its Annex D. NFPA 70 provides different requirements for voltages below 600 volts, between 600 and 1,000 volts, and above 1,000 volts.